Add WebRTC support

Reuse the MediaCaptureDevicesDispatcher from the chrome layer,
pretty much as is, and wire it in with WebContentsDelegateQt and
WebContentsAdapter/WebContentsAdapterClient for API delegation.

We also need to ensure that our user agent string mentions Chrome and
the Chrome version we're based on, in order to please websites that detect
feature support that way.

Change-Id: I0ddf8cd34e4add96bc36f59adfe8e0384e728d93
Reviewed-by: Zeno Albisser <zeno.albisser@digia.com>

14 files changed, 725 insertions, 0 deletions

diff --git a/src/core/chrome_qt.gyp b/src/core/chrome_qt.gyp
new file mode 100644
index 000000000..a38b4a9bf
--- /dev/null
+++ b/src/core/chrome_qt.gyp
@@ -0,0 +1,18 @@
+{
+  'targets': [
+    {
+      'target_name': 'chrome_qt',
+      'type': 'static_library',
+      'include_dirs': [
+        '<(chromium_src_dir)',
+        '<(chromium_src_dir)/skia/config',
+      ],
+      'sources': [
+        '<(chromium_src_dir)/chrome/browser/media/desktop_streams_registry.h',
+        '<(chromium_src_dir)/chrome/browser/media/desktop_streams_registry.cc',
+        '<(chromium_src_dir)/chrome/browser/media/desktop_media_list.h',
+      ],
+    }
+  ],
+}
+
diff --git a/src/core/content_browser_client_qt.cpp b/src/core/content_browser_client_qt.cpp
index 86ff11efb..8945ad0e5 100644
--- a/src/core/content_browser_client_qt.cpp
+++ b/src/core/content_browser_client_qt.cpp
@@ -45,6 +45,7 @@
 #include "base/threading/thread_restrictions.h"
 #include "content/public/browser/browser_main_parts.h"
 #include "content/public/browser/child_process_security_policy.h"
+#include "content/public/browser/media_observer.h"
 #include "content/public/browser/resource_dispatcher_host.h"
 #include "content/public/common/main_function_params.h"
 #include "content/public/common/url_constants.h"
@@ -54,6 +55,7 @@
 
 #include "browser_context_qt.h"
 #include "dev_tools_http_handler_delegate_qt.h"
+#include "media_capture_devices_dispatcher.h"
 #include "resource_dispatcher_host_delegate_qt.h"
 #include "web_contents_view_qt.h"
 
@@ -310,6 +312,11 @@ gfx::GLShareGroup *ContentBrowserClientQt::GetInProcessGpuShareGroup()
     return m_shareGroupQtQuick.get();
 }
 
+content::MediaObserver *ContentBrowserClientQt::GetMediaObserver()
+{
+    return MediaCaptureDevicesDispatcher::GetInstance();
+}
+
 BrowserContextQt* ContentBrowserClientQt::browser_context() {
     Q_ASSERT(m_browserMainParts);
     return static_cast<BrowserMainPartsQt*>(m_browserMainParts)->browser_context();
diff --git a/src/core/content_browser_client_qt.h b/src/core/content_browser_client_qt.h
index c8afc633a..f511eb934 100644
--- a/src/core/content_browser_client_qt.h
+++ b/src/core/content_browser_client_qt.h
@@ -82,6 +82,7 @@ public:
     virtual void RenderProcessHostCreated(content::RenderProcessHost* host) Q_DECL_OVERRIDE;
     virtual void ResourceDispatcherHostCreated() Q_DECL_OVERRIDE;
     virtual gfx::GLShareGroup* GetInProcessGpuShareGroup() Q_DECL_OVERRIDE;
+    virtual content::MediaObserver* GetMediaObserver();
 
     BrowserContextQt* browser_context();
 
diff --git a/src/core/core_gyp_generator.pro b/src/core/core_gyp_generator.pro
index be9bf87c0..c76c707a5 100644
--- a/src/core/core_gyp_generator.pro
+++ b/src/core/core_gyp_generator.pro
@@ -45,6 +45,7 @@ SOURCES = \
         gl_context_qt.cpp \
         javascript_dialog_controller.cpp \
         javascript_dialog_manager_qt.cpp \
+        media_capture_devices_dispatcher.cpp \
         process_main.cpp \
         qt_render_view_observer_host.cpp \
         render_widget_host_view_qt.cpp \
@@ -85,6 +86,7 @@ HEADERS = \
         javascript_dialog_controller_p.h \
         javascript_dialog_controller.h \
         javascript_dialog_manager_qt.h \
+        media_capture_devices_dispatcher.h \
         process_main.h \
         qt_render_view_observer_host.h \
         render_widget_host_view_qt.h \
diff --git a/src/core/media_capture_devices_dispatcher.cpp b/src/core/media_capture_devices_dispatcher.cpp
new file mode 100644
index 000000000..2997576ff
--- /dev/null
+++ b/src/core/media_capture_devices_dispatcher.cpp
@@ -0,0 +1,511 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+
+#include "media_capture_devices_dispatcher.h"
+
+#include "javascript_dialog_manager_qt.h"
+#include "type_conversion.h"
+#include "web_contents_view_qt.h"
+
+#include "base/strings/utf_string_conversions.h"
+#include "chrome/browser/media/desktop_streams_registry.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/desktop_media_id.h"
+#include "content/public/browser/media_devices_monitor.h"
+#include "content/public/browser/notification_service.h"
+#include "content/public/browser/notification_source.h"
+#include "content/public/browser/notification_types.h"
+#include "content/public/browser/web_contents.h"
+#include "content/public/common/media_stream_request.h"
+#include "media/audio/audio_manager_base.h"
+#include "ui/base/l10n/l10n_util.h"
+
+using content::BrowserThread;
+using content::MediaStreamDevices;
+
+namespace {
+
+const content::MediaStreamDevice *findDeviceWithId(const content::MediaStreamDevices &devices, const std::string &deviceId)
+{
+  content::MediaStreamDevices::const_iterator iter = devices.begin();
+  for (; iter != devices.end(); ++iter) {
+    if (iter->id == deviceId) {
+      return &(*iter);
+    }
+  }
+  return 0;
+}
+
+base::string16 getContentsUrl(content::WebContents *webContents)
+{
+  return UTF8ToUTF16(webContents->GetURL().GetOrigin().spec());
+}
+
+scoped_ptr<content::MediaStreamUI> getDevicesForDesktopCapture(content::MediaStreamDevices &devices, content::DesktopMediaID mediaId
+                                                               , bool captureAudio, bool /*display_notification*/, base::string16 /*application_title*/)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  scoped_ptr<content::MediaStreamUI> ui;
+
+  // Add selected desktop source to the list.
+  devices.push_back(content::MediaStreamDevice(
+      content::MEDIA_DESKTOP_VIDEO_CAPTURE, mediaId.ToString(), "Screen"));
+  if (captureAudio) {
+    // Use the special loopback device ID for system audio capture.
+    devices.push_back(content::MediaStreamDevice(
+        content::MEDIA_LOOPBACK_AUDIO_CAPTURE,
+        media::AudioManagerBase::kLoopbackInputDeviceId, "System Audio"));
+  }
+
+  return ui.Pass();
+}
+
+WebContentsAdapterClient::MediaRequestFlags mediaRequestFlagsForRequest(const content::MediaStreamRequest &request)
+{
+    WebContentsAdapterClient::MediaRequestFlags requestFlags;
+    if (request.audio_type == content::MEDIA_DEVICE_AUDIO_CAPTURE)
+        requestFlags |= WebContentsAdapterClient::MediaAudioCapture;
+    if (request.video_type == content::MEDIA_DEVICE_VIDEO_CAPTURE)
+        requestFlags |= WebContentsAdapterClient::MediaVideoCapture;
+    return requestFlags;
+}
+
+}  // namespace
+
+MediaCaptureDevicesDispatcher::PendingAccessRequest::PendingAccessRequest(const content::MediaStreamRequest &request
+                                                                          , const content::MediaResponseCallback &callback)
+    : request(request)
+    , callback(callback)
+{
+}
+
+MediaCaptureDevicesDispatcher::PendingAccessRequest::~PendingAccessRequest()
+{
+}
+
+
+void MediaCaptureDevicesDispatcher::handleMediaAccessPermissionResponse(content::WebContents *webContents, const QUrl &securityOrigin
+                                                                        , WebContentsAdapterClient::MediaRequestFlags authorizationFlags)
+{
+    DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+    content::MediaStreamDevices devices;
+    std::map<content::WebContents*, RequestsQueue>::iterator it = m_pendingRequests.find(webContents);
+
+    if (it == m_pendingRequests.end())
+        // WebContents has been destroyed. Don't need to do anything.
+        return;
+
+    RequestsQueue &queue(it->second);
+    if (queue.empty())
+        return;
+
+    content::MediaStreamRequest &request = queue.front().request;
+
+    const QUrl requestSecurityOrigin(toQt(request.security_origin));
+    bool securityOriginsMatch = (requestSecurityOrigin.host() == securityOrigin.host()
+                                   && requestSecurityOrigin.scheme() == securityOrigin.scheme()
+                                   && requestSecurityOrigin.port() == securityOrigin.port());
+    if (!securityOriginsMatch)
+        qWarning("Security origin mismatch for media access permission: %s requested and %s provided\n", qPrintable(requestSecurityOrigin.toString())
+                 , qPrintable(securityOrigin.toString()));
+
+
+    bool microphoneRequested =
+        (request.audio_type && authorizationFlags & WebContentsAdapterClient::MediaAudioCapture);
+    bool webcamRequested =
+        (request.video_type && authorizationFlags & WebContentsAdapterClient::MediaVideoCapture);
+    if (securityOriginsMatch && (microphoneRequested || webcamRequested)) {
+        switch (request.request_type) {
+        case content::MEDIA_OPEN_DEVICE:
+            Q_UNREACHABLE(); // only speculative as this is for Pepper
+            getDefaultDevices("", "", microphoneRequested, webcamRequested, &devices);
+            break;
+        case content::MEDIA_DEVICE_ACCESS:
+        case content::MEDIA_GENERATE_STREAM:
+        case content::MEDIA_ENUMERATE_DEVICES:
+            getDefaultDevices(request.requested_audio_device_id, request.requested_video_device_id,
+                        microphoneRequested, webcamRequested, &devices);
+            break;
+        }
+    }
+
+    content::MediaResponseCallback callback = queue.front().callback;
+    queue.pop_front();
+
+    if (!queue.empty()) {
+        // Post a task to process next queued request. It has to be done
+        // asynchronously to make sure that calling infobar is not destroyed until
+        // after this function returns.
+        BrowserThread::PostTask(
+                    BrowserThread::UI, FROM_HERE, base::Bind(&MediaCaptureDevicesDispatcher::ProcessQueuedAccessRequest, base::Unretained(this), webContents));
+    }
+
+    callback.Run(devices, scoped_ptr<content::MediaStreamUI>());
+}
+
+
+
+MediaCaptureDevicesDispatcher *MediaCaptureDevicesDispatcher::GetInstance()
+{
+    return Singleton<MediaCaptureDevicesDispatcher>::get();
+}
+
+MediaCaptureDevicesDispatcher::MediaCaptureDevicesDispatcher()
+    : m_devicesEnumerated(false)
+{
+  // MediaCaptureDevicesDispatcher is a singleton. It should be created on
+  // UI thread. Otherwise, it will not receive
+  // content::NOTIFICATION_WEB_CONTENTS_DESTROYED, and that will result in
+  // possible use after free.
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  m_notificationsRegistrar.Add(this, content::NOTIFICATION_WEB_CONTENTS_DESTROYED,
+                               content::NotificationService::AllSources());
+}
+
+MediaCaptureDevicesDispatcher::~MediaCaptureDevicesDispatcher()
+{
+}
+
+const MediaStreamDevices &MediaCaptureDevicesDispatcher::getAudioCaptureDevices()
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (!m_devicesEnumerated) {
+    content::EnsureMonitorCaptureDevices();
+    m_devicesEnumerated = true;
+  }
+  return m_audioDevices;
+}
+
+const MediaStreamDevices &MediaCaptureDevicesDispatcher::getVideoCaptureDevices()
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (!m_devicesEnumerated) {
+    content::EnsureMonitorCaptureDevices();
+    m_devicesEnumerated = true;
+  }
+  return m_videoDevices;
+}
+
+void MediaCaptureDevicesDispatcher::Observe(int type, const content::NotificationSource &source, const content::NotificationDetails &details)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (type == content::NOTIFICATION_WEB_CONTENTS_DESTROYED) {
+    content::WebContents *webContents = content::Source<content::WebContents>(source).ptr();
+    m_pendingRequests.erase(webContents);
+  }
+}
+
+void MediaCaptureDevicesDispatcher::processMediaAccessRequest(WebContentsAdapterClient *adapterClient, content::WebContents *webContents
+                                                              , const content::MediaStreamRequest &request
+                                                              , const content::MediaResponseCallback &callback)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  // Let's not support tab capture for now.
+  if (request.video_type == content::MEDIA_TAB_VIDEO_CAPTURE || request.audio_type == content::MEDIA_TAB_AUDIO_CAPTURE)
+      return;
+
+  if (request.video_type == content::MEDIA_DESKTOP_VIDEO_CAPTURE || request.audio_type == content::MEDIA_LOOPBACK_AUDIO_CAPTURE)
+      // It's still unclear what to make of screen capture. We can rely on existing javascript dialog infrastructure
+      // to experiment with this without exposing it through our API yet.
+      processDesktopCaptureAccessRequest(webContents, request, callback);
+  else {
+      enqueueMediaAccessRequest(webContents, request, callback);
+      // We might not require this approval for pepper requests.
+      adapterClient->runMediaAccessPermissionRequest(toQt(request.security_origin), mediaRequestFlagsForRequest(request));
+  }
+
+}
+
+void MediaCaptureDevicesDispatcher::processDesktopCaptureAccessRequest(content::WebContents *webContents, const content::MediaStreamRequest &request
+                                                                       , const content::MediaResponseCallback &callback)
+{
+  content::MediaStreamDevices devices;
+  scoped_ptr<content::MediaStreamUI> ui;
+
+  if (request.video_type != content::MEDIA_DESKTOP_VIDEO_CAPTURE) {
+    callback.Run(devices, ui.Pass());
+    return;
+  }
+
+  // If the device id wasn't specified then this is a screen capture request
+  // (i.e. chooseDesktopMedia() API wasn't used to generate device id).
+  if (request.requested_video_device_id.empty()) {
+    processScreenCaptureAccessRequest(
+        webContents, request, callback);
+    return;
+  }
+
+  // Resolve DesktopMediaID for the specified device id.
+  content::DesktopMediaID mediaId =
+      getDesktopStreamsRegistry()->RequestMediaForStreamId(
+          request.requested_video_device_id, request.render_process_id,
+          request.render_view_id, request.security_origin);
+
+  // Received invalid device id.
+  if (mediaId.type == content::DesktopMediaID::TYPE_NONE) {
+    callback.Run(devices, ui.Pass());
+    return;
+  }
+
+  // Audio is only supported for screen capture streams.
+  bool capture_audio = (mediaId.type == content::DesktopMediaID::TYPE_SCREEN &&
+       request.audio_type == content::MEDIA_LOOPBACK_AUDIO_CAPTURE);
+
+  ui = getDevicesForDesktopCapture(
+      devices, mediaId, capture_audio, true,
+      getContentsUrl(webContents));
+
+  callback.Run(devices, ui.Pass());
+}
+
+void MediaCaptureDevicesDispatcher::processScreenCaptureAccessRequest(content::WebContents *webContents, const content::MediaStreamRequest &request
+                                                                      ,const content::MediaResponseCallback &callback)
+{
+  DCHECK_EQ(request.video_type, content::MEDIA_DESKTOP_VIDEO_CAPTURE);
+
+  // FIXME: expose through the settings once we have them
+  const bool screenCaptureEnabled = !qgetenv("QT_WEBENGINE_USE_EXPERIMENTAL_SCREEN_CAPTURE").isNull();
+
+  const bool originIsSecure = request.security_origin.SchemeIsSecure();
+
+  if (screenCaptureEnabled && originIsSecure) {
+
+      enqueueMediaAccessRequest(webContents, request, callback);
+      base::Callback<void(bool, const base::string16&)> dialogCallback = base::Bind(&MediaCaptureDevicesDispatcher::handleScreenCaptureAccessRequest,
+                                                                                 base::Unretained(this), base::Unretained(webContents));
+
+      QUrl securityOrigin(toQt(request.security_origin));
+      QString message = QObject::tr("Do you want %1 to share your screen?").arg(securityOrigin.toString());
+      QString title = QObject::tr("%1 Screen Sharing request").arg(securityOrigin.toString());
+      JavaScriptDialogManagerQt::GetInstance()->runDialogForContents(webContents, WebContentsAdapterClient::InternalAuthorizationDialog, message
+                                                                     , QString(), securityOrigin, dialogCallback, title);
+  } else
+      callback.Run(content::MediaStreamDevices(), scoped_ptr<content::MediaStreamUI>());
+}
+
+void MediaCaptureDevicesDispatcher::handleScreenCaptureAccessRequest(content::WebContents *webContents, bool userAccepted, const base::string16 &)
+{
+    content::MediaStreamDevices devices;
+    scoped_ptr<content::MediaStreamUI> ui;
+    if (userAccepted) {
+      content::DesktopMediaID screenId = content::DesktopMediaID(content::DesktopMediaID::TYPE_SCREEN, 0);
+      ui = getDevicesForDesktopCapture(devices, screenId,  false/*capture_audio*/, false/*display_notification*/, getContentsUrl(webContents));
+    }
+    std::map<content::WebContents*, RequestsQueue>::iterator it =
+        m_pendingRequests.find(webContents);
+    if (it == m_pendingRequests.end()) {
+      // WebContents has been destroyed. Don't need to do anything.
+      return;
+    }
+
+    RequestsQueue &queue(it->second);
+    if (queue.empty())
+      return;
+
+    content::MediaResponseCallback callback = queue.front().callback;
+    queue.pop_front();
+
+    callback.Run(devices, ui.Pass());
+}
+
+void MediaCaptureDevicesDispatcher::enqueueMediaAccessRequest(content::WebContents *webContents, const content::MediaStreamRequest &request
+                                                                     ,const content::MediaResponseCallback &callback)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  RequestsQueue &queue = m_pendingRequests[webContents];
+  queue.push_back(PendingAccessRequest(request, callback));
+}
+
+void MediaCaptureDevicesDispatcher::ProcessQueuedAccessRequest(content::WebContents *webContents) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  std::map<content::WebContents*, RequestsQueue>::iterator it =
+      m_pendingRequests.find(webContents);
+
+  if (it == m_pendingRequests.end() || it->second.empty())
+    return;
+
+  RequestsQueue &queue(it->second);
+  if (queue.empty())
+    return;
+
+  content::MediaStreamRequest &request = queue.front().request;
+
+  DCHECK(!it->second.empty());
+  WebContentsAdapterClient *adapterClient = WebContentsViewQt::from(webContents->GetView())->client();
+  adapterClient->runMediaAccessPermissionRequest(toQt(request.security_origin), mediaRequestFlagsForRequest(request));
+}
+
+void MediaCaptureDevicesDispatcher::getDefaultDevices(const std::string &audioDeviceId, const std::string &videoDeviceId, bool audio, bool video
+                                                      , content::MediaStreamDevices *devices)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(audio || video);
+
+  if (audio) {
+    const content::MediaStreamDevices &audioDevices = getAudioCaptureDevices();
+    const content::MediaStreamDevice *device = findDeviceWithId(audioDevices, audioDeviceId);
+    if (!device && !audioDevices.empty())
+        device = &(*audioDevices.begin());
+    if (device)
+      devices->push_back(*device);
+  }
+
+  if (video) {
+    const content::MediaStreamDevices &videoDevices = getVideoCaptureDevices();
+    const content::MediaStreamDevice *device = findDeviceWithId(videoDevices, videoDeviceId);
+    if (!device && !videoDevices.empty())
+      device = &(*videoDevices.begin());
+    if (device)
+      devices->push_back(*device);
+  }
+}
+
+DesktopStreamsRegistry *MediaCaptureDevicesDispatcher::getDesktopStreamsRegistry()
+{
+  if (!m_desktopStreamsRegistry)
+    m_desktopStreamsRegistry.reset(new DesktopStreamsRegistry());
+  return m_desktopStreamsRegistry.get();
+}
+
+void MediaCaptureDevicesDispatcher::OnAudioCaptureDevicesChanged(const content::MediaStreamDevices &devices)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      base::Bind(&MediaCaptureDevicesDispatcher::updateAudioDevicesOnUIThread,
+                 base::Unretained(this), devices));
+}
+
+void MediaCaptureDevicesDispatcher::OnVideoCaptureDevicesChanged(const content::MediaStreamDevices &devices)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      base::Bind(&MediaCaptureDevicesDispatcher::updateVideoDevicesOnUIThread,
+                 base::Unretained(this), devices));
+}
+
+void MediaCaptureDevicesDispatcher::OnMediaRequestStateChanged(int renderProcessId, int renderViewId, int pageRequestId
+                                                               , const content::MediaStreamDevice &device, content::MediaRequestState state)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      base::Bind(
+          &MediaCaptureDevicesDispatcher::updateMediaRequestStateOnUIThread,
+          base::Unretained(this), renderProcessId, renderViewId,
+          pageRequestId, device, state));
+}
+
+void MediaCaptureDevicesDispatcher::OnCreatingAudioStream(int /*renderProcessId*/, int /*renderViewId*/)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+}
+
+void MediaCaptureDevicesDispatcher::updateAudioDevicesOnUIThread(const content::MediaStreamDevices &devices)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  m_devicesEnumerated = true;
+  m_audioDevices = devices;
+}
+
+void MediaCaptureDevicesDispatcher::updateVideoDevicesOnUIThread(const content::MediaStreamDevices &devices)
+{
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  m_devicesEnumerated = true;
+  m_videoDevices = devices;
+}
+
+void MediaCaptureDevicesDispatcher::updateMediaRequestStateOnUIThread(int renderProcessId, int renderViewId, int pageRequestId
+                                                                      , const content::MediaStreamDevice &device, content::MediaRequestState state)
+{
+  // Track desktop capture sessions.  Tracking is necessary to avoid unbalanced
+  // session counts since not all requests will reach MEDIA_REQUEST_STATE_DONE,
+  // but they will all reach MEDIA_REQUEST_STATE_CLOSING.
+  if (device.type == content::MEDIA_DESKTOP_VIDEO_CAPTURE) {
+    if (state == content::MEDIA_REQUEST_STATE_DONE) {
+      DesktopCaptureSession session = { renderProcessId, renderViewId,
+                                        pageRequestId };
+      m_desktopCaptureSessions.push_back(session);
+    } else if (state == content::MEDIA_REQUEST_STATE_CLOSING) {
+      for (DesktopCaptureSessions::iterator it =
+               m_desktopCaptureSessions.begin();
+           it != m_desktopCaptureSessions.end();
+           ++it) {
+        if (it->render_process_id == renderProcessId &&
+            it->render_view_id == renderViewId &&
+            it->page_request_id == pageRequestId) {
+          m_desktopCaptureSessions.erase(it);
+          break;
+        }
+      }
+    }
+  }
+
+  // Cancel the request.
+  if (state == content::MEDIA_REQUEST_STATE_CLOSING) {
+    bool found = false;
+    for (RequestsQueues::iterator rqs_it = m_pendingRequests.begin();
+         rqs_it != m_pendingRequests.end(); ++rqs_it) {
+      RequestsQueue &queue = rqs_it->second;
+      for (RequestsQueue::iterator it = queue.begin();
+           it != queue.end(); ++it) {
+        if (it->request.render_process_id == renderProcessId &&
+            it->request.render_view_id == renderViewId &&
+            it->request.page_request_id == pageRequestId) {
+          queue.erase(it);
+          found = true;
+          break;
+        }
+      }
+      if (found)
+        break;
+    }
+  }
+}
diff --git a/src/core/media_capture_devices_dispatcher.h b/src/core/media_capture_devices_dispatcher.h
new file mode 100644
index 000000000..38d7b1c19
--- /dev/null
+++ b/src/core/media_capture_devices_dispatcher.h
@@ -0,0 +1,159 @@
+/****************************************************************************
+**
+** Copyright (c) 2012 The Chromium Authors. All rights reserved.
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtWebEngine module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Digia.  For licensing terms and
+** conditions see http://qt.digia.com/licensing.  For further information
+** use the contact form at http://qt.digia.com/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights.  These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef MEDIA_CAPTURE_DEVICES_DISPATCHER_H
+#define MEDIA_CAPTURE_DEVICES_DISPATCHER_H
+
+#include <deque>
+#include <list>
+#include <map>
+#include <QtCore/qcompilerdetection.h>
+
+#include "web_contents_adapter_client.h"
+
+#include "base/callback.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/singleton.h"
+#include "base/observer_list.h"
+#include "content/public/browser/media_observer.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
+#include "content/public/browser/web_contents_delegate.h"
+#include "content/public/common/media_stream_request.h"
+
+class AudioStreamIndicator;
+class DesktopStreamsRegistry;
+class MediaStreamCaptureIndicator;
+
+// This singleton is used to receive updates about media events from the content
+// layer. Based on Chrome's implementation.
+class MediaCaptureDevicesDispatcher : public content::MediaObserver,
+                                      public content::NotificationObserver {
+ public:
+
+  static MediaCaptureDevicesDispatcher *GetInstance();
+
+  void processMediaAccessRequest(WebContentsAdapterClient *, content::WebContents *, const content::MediaStreamRequest &, const content::MediaResponseCallback &);
+
+  // Called back from our WebContentsAdapter to grant the requested permission.
+  void handleMediaAccessPermissionResponse(content::WebContents *, const QUrl &securityOrigin, WebContentsAdapterClient::MediaRequestFlags);
+
+  void getDefaultDevices(const std::string &audioDeviceId, const std::string &videoDeviceId, bool audio, bool video, content::MediaStreamDevices *);
+
+  // Overridden from content::MediaObserver:
+  virtual void OnAudioCaptureDevicesChanged(const content::MediaStreamDevices &) Q_DECL_OVERRIDE;
+  virtual void OnVideoCaptureDevicesChanged(const content::MediaStreamDevices &) Q_DECL_OVERRIDE;
+  virtual void OnMediaRequestStateChanged(int renderProcessId, int renderViewId, int pageRequestId, const content::MediaStreamDevice &device
+                                          , content::MediaRequestState state) Q_DECL_OVERRIDE;
+  virtual void OnAudioStreamPlayingChanged(int /*render_process_id*/, int /*render_view_id*/, int /*stream_id*/
+                                           , bool /*is_playing*/, float /*power_dBFS*/, bool /*clipped*/) Q_DECL_OVERRIDE {}
+  virtual void OnCreatingAudioStream(int renderProcessId, int renderViewId) Q_DECL_OVERRIDE;
+
+  DesktopStreamsRegistry *getDesktopStreamsRegistry();
+
+ private:
+  friend struct DefaultSingletonTraits<MediaCaptureDevicesDispatcher>;
+
+  struct PendingAccessRequest {
+    PendingAccessRequest(const content::MediaStreamRequest &request,
+                         const content::MediaResponseCallback &callback);
+    ~PendingAccessRequest();
+
+    content::MediaStreamRequest request;
+    content::MediaResponseCallback callback;
+  };
+  typedef std::deque<PendingAccessRequest> RequestsQueue;
+  typedef std::map<content::WebContents *, RequestsQueue> RequestsQueues;
+
+  MediaCaptureDevicesDispatcher();
+  virtual ~MediaCaptureDevicesDispatcher();
+
+  const content::MediaStreamDevices &getAudioCaptureDevices();
+  const content::MediaStreamDevices &getVideoCaptureDevices();
+
+  // content::NotificationObserver implementation.
+  virtual void Observe(int type, const content::NotificationSource &source, const content::NotificationDetails &details) Q_DECL_OVERRIDE;
+
+  // Helpers for ProcessMediaAccessRequest().
+  void processDesktopCaptureAccessRequest(content::WebContents *, const content::MediaStreamRequest &, const content::MediaResponseCallback &);
+  void processScreenCaptureAccessRequest(content::WebContents *,const content::MediaStreamRequest &, const content::MediaResponseCallback &);
+  void handleScreenCaptureAccessRequest(content::WebContents *, bool userAccepted, const base::string16 &/*unused callback_input*/);
+  void enqueueMediaAccessRequest(content::WebContents *, const content::MediaStreamRequest &, const content::MediaResponseCallback &);
+  void ProcessQueuedAccessRequest(content::WebContents *);
+
+  // Called by the MediaObserver() functions, executed on UI thread.
+  void updateAudioDevicesOnUIThread(const content::MediaStreamDevices &);
+  void updateVideoDevicesOnUIThread(const content::MediaStreamDevices &);
+  void updateMediaRequestStateOnUIThread(int renderProcessId, int renderViewId, int pageRequestId, const content::MediaStreamDevice &
+                                         , content::MediaRequestState);
+
+  // A list of cached audio capture devices.
+  content::MediaStreamDevices m_audioDevices;
+
+  // A list of cached video capture devices.
+  content::MediaStreamDevices m_videoDevices;
+
+  // Flag to indicate if device enumeration has been done/doing.
+  // Only accessed on UI thread.
+  bool m_devicesEnumerated;
+
+  RequestsQueues m_pendingRequests;
+
+  scoped_ptr<DesktopStreamsRegistry> m_desktopStreamsRegistry;
+
+  content::NotificationRegistrar m_notificationsRegistrar;
+
+  // Tracks MEDIA_DESKTOP_VIDEO_CAPTURE sessions which reach the
+  // MEDIA_REQUEST_STATE_DONE state.  Sessions are remove when
+  // MEDIA_REQUEST_STATE_CLOSING is encountered.
+  struct DesktopCaptureSession {
+    int render_process_id;
+    int render_view_id;
+    int page_request_id;
+  };
+  typedef std::list<DesktopCaptureSession> DesktopCaptureSessions;
+  DesktopCaptureSessions m_desktopCaptureSessions;
+
+  DISALLOW_COPY_AND_ASSIGN(MediaCaptureDevicesDispatcher);
+};
+
+#endif  // MEDIA_CAPTURE_DEVICES_DISPATCHER_H
diff --git a/src/core/qtwebengine.gypi b/src/core/qtwebengine.gypi
index fee9d37dd..c01998c59 100644
--- a/src/core/qtwebengine.gypi
+++ b/src/core/qtwebengine.gypi
@@ -28,6 +28,7 @@
       '<(chromium_src_dir)/v8/tools/gyp/v8.gyp:v8',
       '<(chromium_src_dir)/webkit/glue/webkit_glue.gyp:*',
       '<(chromium_src_dir)/third_party/WebKit/Source/web/web.gyp:webkit',
+      'chrome_qt.gyp:*',
     ],
     'include_dirs': [
       '<(chromium_src_dir)',
diff --git a/src/core/web_contents_adapter.cpp b/src/core/web_contents_adapter.cpp
index ff0b9a83d..11b5f7cc2 100644
--- a/src/core/web_contents_adapter.cpp
+++ b/src/core/web_contents_adapter.cpp
@@ -48,6 +48,7 @@
 #include "browser_context_qt.h"
 #include "content_browser_client_qt.h"
 #include "javascript_dialog_manager_qt.h"
+#include "media_capture_devices_dispatcher.h"
 #include "qt_render_view_observer_host.h"
 #include "type_conversion.h"
 #include "web_contents_adapter_client.h"
@@ -676,6 +677,12 @@ void WebContentsAdapter::wasHidden()
     d->webContents->WasHidden();
 }
 
+void WebContentsAdapter::grantMediaAccessPermission(const QUrl &securityOrigin, WebContentsAdapterClient::MediaRequestFlags flags)
+{
+    Q_D(WebContentsAdapter);
+    MediaCaptureDevicesDispatcher::GetInstance()->handleMediaAccessPermissionResponse(d->webContents.get(), securityOrigin, flags);
+}
+
 void WebContentsAdapter::dpiScaleChanged()
 {
     Q_D(WebContentsAdapter);
diff --git a/src/core/web_contents_adapter.h b/src/core/web_contents_adapter.h
index fc6ea99fb..b6984933e 100644
--- a/src/core/web_contents_adapter.h
+++ b/src/core/web_contents_adapter.h
@@ -106,6 +106,7 @@ public:
 
     void wasShown();
     void wasHidden();
+    void grantMediaAccessPermission(const QUrl &securityOrigin, WebContentsAdapterClient::MediaRequestFlags flags);
 
     void dpiScaleChanged();
 
diff --git a/src/core/web_contents_adapter_client.h b/src/core/web_contents_adapter_client.h
index 64b5fca38..44668b539 100644
--- a/src/core/web_contents_adapter_client.h
+++ b/src/core/web_contents_adapter_client.h
@@ -43,6 +43,7 @@
 
 #include "qtwebenginecoreglobal.h"
 
+#include <QFlags>
 #include <QRect>
 #include <QSharedPointer>
 #include <QString>
@@ -115,6 +116,13 @@ public:
         Error
     };
 
+    enum MediaRequestFlag {
+        MediaNone = 0,
+        MediaAudioCapture = 0x01,
+        MediaVideoCapture = 0x02,
+    };
+    Q_DECLARE_FLAGS(MediaRequestFlags, MediaRequestFlag)
+
     virtual ~WebContentsAdapterClient() { }
 
     virtual RenderWidgetHostViewQtDelegate* CreateRenderWidgetHostViewQtDelegate(RenderWidgetHostViewQtDelegateClient *client) = 0;
@@ -145,6 +153,7 @@ public:
     virtual void passOnFocus(bool reverse) = 0;
     virtual void javaScriptConsoleMessage(JavaScriptConsoleMessageLevel level, const QString& message, int lineNumber, const QString& sourceID) = 0;
     virtual void authenticationRequired(const QUrl &requestUrl, const QString &realm, bool isProxy, const QString &challengingHost, QString *outUser, QString *outPassword) = 0;
+    virtual void runMediaAccessPermissionRequest(const QUrl &securityOrigin, MediaRequestFlags requestFlags) = 0;
 };
 
 #endif // WEB_CONTENTS_ADAPTER_CLIENT_H
diff --git a/src/core/web_contents_delegate_qt.cpp b/src/core/web_contents_delegate_qt.cpp
index 6e19fd9ab..756646be6 100644
--- a/src/core/web_contents_delegate_qt.cpp
+++ b/src/core/web_contents_delegate_qt.cpp
@@ -45,6 +45,7 @@
 
 #include "web_contents_delegate_qt.h"
 
+#include "media_capture_devices_dispatcher.h"
 #include "type_conversion.h"
 #include "web_contents_adapter.h"
 #include "web_contents_adapter_client.h"
@@ -235,3 +236,8 @@ void WebContentsDelegateQt::FindReply(content::WebContents *source, int request_
     if (final_update)
         m_viewClient->didFindText(request_id, number_of_matches);
 }
+
+void WebContentsDelegateQt::RequestMediaAccessPermission(content::WebContents *web_contents, const content::MediaStreamRequest &request, const content::MediaResponseCallback &callback)
+{
+    MediaCaptureDevicesDispatcher::GetInstance()->processMediaAccessRequest(m_viewClient, web_contents, request, callback);
+}
diff --git a/src/core/web_contents_delegate_qt.h b/src/core/web_contents_delegate_qt.h
index fe36088eb..255428778 100644
--- a/src/core/web_contents_delegate_qt.h
+++ b/src/core/web_contents_delegate_qt.h
@@ -80,6 +80,7 @@ public:
     virtual void RunFileChooser(content::WebContents *, const content::FileChooserParams &params) Q_DECL_OVERRIDE;
     virtual bool AddMessageToConsole(content::WebContents* source, int32 level, const base::string16& message, int32 line_no, const base::string16& source_id) Q_DECL_OVERRIDE;
     virtual void FindReply(content::WebContents *source, int request_id, int number_of_matches, const gfx::Rect& selection_rect, int active_match_ordinal, bool final_update) Q_DECL_OVERRIDE;
+    virtual void RequestMediaAccessPermission(content::WebContents* web_contents, const content::MediaStreamRequest& request, const content::MediaResponseCallback& callback) Q_DECL_OVERRIDE;
 
 private:
     WebContentsAdapterClient *m_viewClient;
diff --git a/src/webengine/api/qquickwebengineview_p_p.h b/src/webengine/api/qquickwebengineview_p_p.h
index 4cbca6594..cde8d297d 100644
--- a/src/webengine/api/qquickwebengineview_p_p.h
+++ b/src/webengine/api/qquickwebengineview_p_p.h
@@ -153,6 +153,7 @@ public:
     virtual void passOnFocus(bool reverse) Q_DECL_OVERRIDE;
     virtual void javaScriptConsoleMessage(JavaScriptConsoleMessageLevel level, const QString& message, int lineNumber, const QString& sourceID) Q_DECL_OVERRIDE;
     virtual void authenticationRequired(const QUrl&, const QString&, bool, const QString&, QString*, QString*) Q_DECL_OVERRIDE { }
+    virtual void runMediaAccessPermissionRequest(const QUrl &securityOrigin, MediaRequestFlags requestFlags) Q_DECL_OVERRIDE { }
 
     void setDevicePixelRatio(qreal);
     void adoptWebContents(WebContentsAdapter *webContents);
diff --git a/src/webenginewidgets/api/qwebenginepage_p.h b/src/webenginewidgets/api/qwebenginepage_p.h
index ddc7c51e7..0c4d3b850 100644
--- a/src/webenginewidgets/api/qwebenginepage_p.h
+++ b/src/webenginewidgets/api/qwebenginepage_p.h
@@ -136,6 +136,7 @@ public:
     virtual void passOnFocus(bool reverse) Q_DECL_OVERRIDE { Q_UNUSED(reverse); };
     virtual void javaScriptConsoleMessage(JavaScriptConsoleMessageLevel level, const QString& message, int lineNumber, const QString& sourceID) Q_DECL_OVERRIDE;
     virtual void authenticationRequired(const QUrl &requestUrl, const QString &realm, bool isProxy, const QString &challengingHost, QString *outUser, QString *outPassword) Q_DECL_OVERRIDE;
+    virtual void runMediaAccessPermissionRequest(const QUrl &securityOrigin, MediaRequestFlags requestFlags) Q_DECL_OVERRIDE {};
 
     void updateAction(QWebEnginePage::WebAction) const;
     void updateNavigationActions();