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>

1 files changed, 159 insertions, 0 deletions

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