Add QQuickWebEngineFaviconProvider

The new QQuickImageProvider subclass is used to access downloaded icons
from the FaviconManager via the Quick API.

Change-Id: I6a52d3c737b2260cf480167764a931915cd99cab
Task-number: QTBUG-51179
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@theqtcompany.com>

15 files changed, 415 insertions, 15 deletions

diff --git a/examples/webengine/quicknanobrowser/BrowserWindow.qml b/examples/webengine/quicknanobrowser/BrowserWindow.qml
index b468b2a77..c008425d9 100644
--- a/examples/webengine/quicknanobrowser/BrowserWindow.qml
+++ b/examples/webengine/quicknanobrowser/BrowserWindow.qml
@@ -237,6 +237,7 @@ ApplicationWindow {
                         z: 2
                         id: faviconImage
                         width: 16; height: 16
+                        sourceSize: Qt.size(width, height)
                         source: currentWebView && currentWebView.icon
                     }
                     style: TextFieldStyle {
diff --git a/src/core/favicon_manager.cpp b/src/core/favicon_manager.cpp
index 16a087efc..5568e6eb5 100644
--- a/src/core/favicon_manager.cpp
+++ b/src/core/favicon_manager.cpp
@@ -220,11 +220,15 @@ FaviconManager::~FaviconManager()
 QIcon FaviconManager::getIcon(const QUrl &url) const
 {
     Q_D(const FaviconManager);
+    if (!d->m_icons.contains(url))
+        return QIcon();
+
     return d->m_icons[url];
 }
 
 FaviconInfo FaviconManager::getFaviconInfo(const QUrl &url) const
 {
+    Q_ASSERT(m_faviconInfoMap.contains(url));
     return m_faviconInfoMap[url];
 }
 
diff --git a/src/webengine/api/qquickwebenginefaviconprovider.cpp b/src/webengine/api/qquickwebenginefaviconprovider.cpp
new file mode 100644
index 000000000..c41ec5a07
--- /dev/null
+++ b/src/webengine/api/qquickwebenginefaviconprovider.cpp
@@ -0,0 +1,186 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/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 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qquickwebenginefaviconprovider_p_p.h"
+
+#include "favicon_manager.h"
+#include "qquickwebengineview_p.h"
+#include "qquickwebengineview_p_p.h"
+#include "web_contents_adapter.h"
+
+#include <QtGui/QIcon>
+#include <QtGui/QPixmap>
+
+QT_BEGIN_NAMESPACE
+
+using QtWebEngineCore::FaviconInfo;
+using QtWebEngineCore::FaviconManager;
+
+static inline unsigned area(const QSize &size)
+{
+    return size.width() * size.height();
+}
+
+QString QQuickWebEngineFaviconProvider::identifier()
+{
+    return QStringLiteral("favicon");
+}
+
+QUrl QQuickWebEngineFaviconProvider::faviconProviderUrl(const QUrl &url)
+{
+    if (url.isEmpty())
+        return url;
+
+    QUrl providerUrl;
+    providerUrl.setScheme(QStringLiteral("image"));
+    providerUrl.setHost(identifier());
+    providerUrl.setPath(QStringLiteral("/%1").arg(url.toString()));
+
+    return providerUrl;
+}
+
+QQuickWebEngineFaviconProvider::QQuickWebEngineFaviconProvider()
+    : QQuickImageProvider(QQuickImageProvider::Pixmap)
+    , m_latestView(0)
+{
+}
+
+QQuickWebEngineFaviconProvider::~QQuickWebEngineFaviconProvider()
+{
+    qDeleteAll(m_iconUrlMap);
+}
+
+QUrl QQuickWebEngineFaviconProvider::attach(QQuickWebEngineView *view, const QUrl &iconUrl)
+{
+    if (iconUrl.isEmpty())
+        return QUrl();
+
+    m_latestView = view;
+
+    if (!m_iconUrlMap.contains(view))
+        m_iconUrlMap.insert(view, new QList<QUrl>());
+
+    QList<QUrl> *iconUrls = m_iconUrlMap[view];
+    if (!iconUrls->contains(iconUrl))
+        iconUrls->append(iconUrl);
+
+    return faviconProviderUrl(iconUrl);
+}
+
+void QQuickWebEngineFaviconProvider::detach(QQuickWebEngineView *view)
+{
+    QList<QUrl> *iconUrls = m_iconUrlMap.take(view);
+    delete iconUrls;
+}
+
+QPixmap QQuickWebEngineFaviconProvider::requestPixmap(const QString &id, QSize *size, const QSize &requestedSize)
+{
+    Q_UNUSED(size);
+    Q_UNUSED(requestedSize);
+
+    QUrl iconUrl(id);
+    QQuickWebEngineView *view = viewForIconUrl(iconUrl);
+
+    if (!view || iconUrl.isEmpty())
+        return QPixmap();
+
+    FaviconManager *faviconManager = view->d_ptr->adapter->faviconManager();
+    Q_ASSERT(faviconManager);
+
+    const QIcon &icon = faviconManager->getIcon(iconUrl);
+
+    Q_ASSERT(!icon.isNull());
+    const QSize &bestSize = faviconManager->getFaviconInfo(iconUrl).size;
+
+    // If source size is not specified, use the best quality
+    if (!requestedSize.isValid()) {
+        if (size)
+            *size = bestSize;
+
+        return icon.pixmap(bestSize).copy();
+    }
+
+    const QSize &fitSize = findFitSize(icon.availableSizes(), requestedSize, bestSize);
+    const QPixmap &iconPixmap = icon.pixmap(fitSize);
+
+    if (size)
+        *size = iconPixmap.size();
+
+    return iconPixmap.scaled(requestedSize, Qt::KeepAspectRatio, Qt::SmoothTransformation).copy();
+}
+
+QQuickWebEngineView *QQuickWebEngineFaviconProvider::viewForIconUrl(const QUrl &iconUrl) const
+{
+    // The most common use case is that the requested iconUrl belongs to the
+    // latest WebEngineView which was raised an iconChanged signal.
+    if (m_latestView) {
+        QList<QUrl> *iconUrls = m_iconUrlMap[m_latestView];
+        if (iconUrls->contains(iconUrl))
+            return m_latestView;
+    }
+
+    for (auto it = m_iconUrlMap.cbegin(), end = m_iconUrlMap.cend(); it != end; ++it) {
+        if (it.value()->contains(iconUrl))
+            return it.key();
+    }
+
+    return 0;
+}
+
+QSize QQuickWebEngineFaviconProvider::findFitSize(const QList<QSize> &availableSizes,
+                                                  const QSize &requestedSize,
+                                                  const QSize &bestSize) const
+{
+    Q_ASSERT(availableSizes.count());
+    if (availableSizes.count() == 1 || area(requestedSize) >= area(bestSize))
+        return bestSize;
+
+    QSize fitSize = bestSize;
+    for (const QSize &size : availableSizes) {
+        if (area(size) == area(requestedSize))
+            return size;
+
+        if (area(requestedSize) < area(size) && area(size) < area(fitSize))
+            fitSize = size;
+    }
+
+    return fitSize;
+}
+
+QT_END_NAMESPACE
diff --git a/src/webengine/api/qquickwebenginefaviconprovider_p_p.h b/src/webengine/api/qquickwebenginefaviconprovider_p_p.h
new file mode 100644
index 000000000..52f3fb7a9
--- /dev/null
+++ b/src/webengine/api/qquickwebenginefaviconprovider_p_p.h
@@ -0,0 +1,87 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/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 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QQUICKWEBENGINEFAVICONPROVIDER_P_P_H
+#define QQUICKWEBENGINEFAVICONPROVIDER_P_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <private/qtwebengineglobal_p.h>
+#include <QtQuick/QQuickImageProvider>
+
+#include <QtCore/QMap>
+
+QT_BEGIN_NAMESPACE
+
+class QQuickWebEngineView;
+
+class Q_WEBENGINE_PRIVATE_EXPORT QQuickWebEngineFaviconProvider : public QQuickImageProvider {
+public:
+    static QString identifier();
+    static QUrl faviconProviderUrl(const QUrl &);
+
+    QQuickWebEngineFaviconProvider();
+    ~QQuickWebEngineFaviconProvider();
+
+    QUrl attach(QQuickWebEngineView *, const QUrl &);
+    void detach(QQuickWebEngineView *);
+
+
+    virtual QPixmap requestPixmap(const QString &, QSize *, const QSize &);
+
+private:
+    QQuickWebEngineView *viewForIconUrl(const QUrl &) const;
+    QSize findFitSize(const QList<QSize> &, const QSize &, const QSize &) const;
+
+    QMap<QQuickWebEngineView *, QList<QUrl> *> m_iconUrlMap;
+    QQuickWebEngineView *m_latestView;
+};
+
+QT_END_NAMESPACE
+
+#endif // QQUICKWEBENGINEFAVICONPROVIDER_P_P_H
diff --git a/src/webengine/api/qquickwebengineview.cpp b/src/webengine/api/qquickwebengineview.cpp
index 9296cc4dd..122ae2350 100644
--- a/src/webengine/api/qquickwebengineview.cpp
+++ b/src/webengine/api/qquickwebengineview.cpp
@@ -47,6 +47,7 @@
 #include "javascript_dialog_controller.h"
 #include "qquickwebenginehistory_p.h"
 #include "qquickwebenginecertificateerror_p.h"
+#include "qquickwebenginefaviconprovider_p_p.h"
 #include "qquickwebengineloadrequest_p.h"
 #include "qquickwebenginenavigationrequest_p.h"
 #include "qquickwebenginenewviewrequest_p.h"
@@ -112,6 +113,7 @@ QQuickWebEngineViewPrivate::QQuickWebEngineViewPrivate()
     , m_testSupport(0)
 #endif
     , contextMenuExtraItems(0)
+    , faviconProvider(0)
     , loadProgress(0)
     , m_fullscreenMode(false)
     , isLoading(false)
@@ -389,9 +391,19 @@ void QQuickWebEngineViewPrivate::urlChanged(const QUrl &url)
 void QQuickWebEngineViewPrivate::iconChanged(const QUrl &url)
 {
     Q_Q(QQuickWebEngineView);
-    if (iconUrl == url)
+
+    if (iconUrl == QQuickWebEngineFaviconProvider::faviconProviderUrl(url))
         return;
-    iconUrl = url;
+
+    if (!faviconProvider) {
+        QQmlEngine *engine = qmlEngine(q);
+        Q_ASSERT(engine);
+        faviconProvider = static_cast<QQuickWebEngineFaviconProvider *>(
+                    engine->imageProvider(QQuickWebEngineFaviconProvider::identifier()));
+        Q_ASSERT(faviconProvider);
+    }
+
+    iconUrl = faviconProvider->attach(q, url);
     Q_EMIT q->iconChanged();
 }
 
@@ -788,6 +800,9 @@ QQuickWebEngineView::QQuickWebEngineView(QQuickItem *parent)
 
 QQuickWebEngineView::~QQuickWebEngineView()
 {
+    Q_D(QQuickWebEngineView);
+    if (d->faviconProvider)
+        d->faviconProvider->detach(this);
 }
 
 void QQuickWebEngineViewPrivate::ensureContentsAdapter()
diff --git a/src/webengine/api/qquickwebengineview_p.h b/src/webengine/api/qquickwebengineview_p.h
index 8015820b7..843e34f42 100644
--- a/src/webengine/api/qquickwebengineview_p.h
+++ b/src/webengine/api/qquickwebengineview_p.h
@@ -60,6 +60,7 @@ QT_BEGIN_NAMESPACE
 class QQmlWebChannel;
 class QQuickWebEngineCertificateError;
 class QQuickWebEngineContextMenuData;
+class QQuickWebEngineFaviconProvider;
 class QQuickWebEngineHistory;
 class QQuickWebEngineLoadRequest;
 class QQuickWebEngineNavigationRequest;
@@ -517,6 +518,7 @@ private:
     friend class QQuickWebEngineViewExperimental;
     friend class QQuickWebEngineViewExperimentalExtension;
     friend class QQuickWebEngineNewViewRequest;
+    friend class QQuickWebEngineFaviconProvider;
 #ifndef QT_NO_ACCESSIBILITY
     friend class QQuickWebEngineViewAccessible;
 #endif // QT_NO_ACCESSIBILITY
diff --git a/src/webengine/api/qquickwebengineview_p_p.h b/src/webengine/api/qquickwebengineview_p_p.h
index d240e3e50..892e99cb9 100644
--- a/src/webengine/api/qquickwebengineview_p_p.h
+++ b/src/webengine/api/qquickwebengineview_p_p.h
@@ -71,6 +71,7 @@ class QQuickWebEngineView;
 class QQmlComponent;
 class QQmlContext;
 class QQuickWebEngineSettings;
+class QQuickWebEngineFaviconProvider;
 
 #ifdef ENABLE_QML_TESTSUPPORT_API
 class QQuickWebEngineTestSupport;
@@ -215,6 +216,7 @@ public:
     QQuickWebEngineContextMenuData contextMenuData;
     QUrl explicitUrl;
     QUrl iconUrl;
+    QQuickWebEngineFaviconProvider *faviconProvider;
     int loadProgress;
     bool m_fullscreenMode;
     bool isLoading;
diff --git a/src/webengine/doc/src/webengineview.qdoc b/src/webengine/doc/src/webengineview.qdoc
index 3bebb8cea..a070140c7 100644
--- a/src/webengine/doc/src/webengineview.qdoc
+++ b/src/webengine/doc/src/webengineview.qdoc
@@ -203,10 +203,11 @@
     \qmlproperty url WebEngineView::icon
     \readonly
 
-    The location of the currently displayed web site icon,
-    also known as favicon or shortcut icon. This read-only URL corresponds to
-    the image used within a mobile browser application to represent a
-    bookmarked page on the device's home screen.
+    An internal URL for accessing the currently displayed web site icon,
+    also known as favicon or shortcut icon. The icon is already downloaded
+    and stored by the Qt WebEngine's favicon manager.
+    This read-only URL corresponds to the image used within a mobile browser
+    application to represent a bookmarked page on the device's home screen.
 
     The following snippet uses the \c{icon} property to build an \c{Image}
     component:
@@ -214,7 +215,7 @@
     \qml
     Image {
         id: appIcon
-        source: webView.icon != "" ? webView.icon : "fallbackFavIcon.png";
+        source: webView.icon != "" ? webView.icon : "fallbackFavicon.png";
         // ...
     }
     \endqml
diff --git a/src/webengine/plugin/plugin.cpp b/src/webengine/plugin/plugin.cpp
index fc8e40bd0..b71689a34 100644
--- a/src/webengine/plugin/plugin.cpp
+++ b/src/webengine/plugin/plugin.cpp
@@ -43,6 +43,7 @@
 #include "qquickwebenginecertificateerror_p.h"
 #include "qquickwebenginedownloaditem_p.h"
 #include "qquickwebenginehistory_p.h"
+#include "qquickwebenginefaviconprovider_p_p.h"
 #include "qquickwebengineloadrequest_p.h"
 #include "qquickwebenginenavigationrequest_p.h"
 #include "qquickwebenginenewviewrequest_p.h"
@@ -63,6 +64,12 @@ class QtWebEnginePlugin : public QQmlExtensionPlugin
     Q_OBJECT
     Q_PLUGIN_METADATA(IID "org.qt-project.Qt.QQmlExtensionInterface/1.0")
 public:
+    virtual void initializeEngine(QQmlEngine *engine, const char *uri)
+    {
+        Q_UNUSED(uri);
+        engine->addImageProvider(QQuickWebEngineFaviconProvider::identifier(), new QQuickWebEngineFaviconProvider);
+    }
+
     virtual void registerTypes(const char *uri) Q_DECL_OVERRIDE
     {
         Q_ASSERT(QLatin1String(uri) == QLatin1String("QtWebEngine"));
diff --git a/src/webengine/webengine.pro b/src/webengine/webengine.pro
index e4b274a82..236881958 100644
--- a/src/webengine/webengine.pro
+++ b/src/webengine/webengine.pro
@@ -15,6 +15,7 @@ SOURCES = \
         api/qquickwebenginecontextmenudata.cpp \
         api/qquickwebenginedownloaditem.cpp \
         api/qquickwebenginehistory.cpp \
+        api/qquickwebenginefaviconprovider.cpp \
         api/qquickwebengineloadrequest.cpp \
         api/qquickwebenginenavigationrequest.cpp \
         api/qquickwebenginenewviewrequest.cpp \
@@ -36,6 +37,7 @@ HEADERS = \
         api/qquickwebenginedownloaditem_p.h \
         api/qquickwebenginedownloaditem_p_p.h \
         api/qquickwebenginehistory_p.h \
+        api/qquickwebenginefaviconprovider_p_p.h \
         api/qquickwebengineloadrequest_p.h \
         api/qquickwebenginenavigationrequest_p.h \
         api/qquickwebenginenewviewrequest_p.h \
diff --git a/tests/auto/quick/qmltests/data/favicon-multi-gray.html b/tests/auto/quick/qmltests/data/favicon-multi-gray.html
new file mode 100644
index 000000000..d6ac0909f
--- /dev/null
+++ b/tests/auto/quick/qmltests/data/favicon-multi-gray.html
@@ -0,0 +1,9 @@
+<html>
+    <head>
+        <title>Gray Multi-sized Favicon Test</title>
+        <link rel="shortcut icon" href="icons/grayicons.ico" />
+    </head>
+    <body>
+        <h1>Gray Multi-sized Favicon Test</h1>
+    </body>
+</html>
diff --git a/tests/auto/quick/qmltests/data/icons/grayicons.ico b/tests/auto/quick/qmltests/data/icons/grayicons.ico
new file mode 100644
index 000000000..8d8fee839
--- /dev/null
+++ b/tests/auto/quick/qmltests/data/icons/grayicons.ico
diff --git a/tests/auto/quick/qmltests/data/tst_favicon.qml b/tests/auto/quick/qmltests/data/tst_favicon.qml
index 26e39f48c..e959f19be 100644
--- a/tests/auto/quick/qmltests/data/tst_favicon.qml
+++ b/tests/auto/quick/qmltests/data/tst_favicon.qml
@@ -50,6 +50,10 @@ TestWebEngineView {
         }
     }
 
+    function removeFaviconProviderPrefix(url) {
+        return url.toString().substring(16)
+    }
+
     SignalSpy {
         id: iconChangedSpy
         target: webEngineView
@@ -64,6 +68,7 @@ TestWebEngineView {
     TestCase {
         id: test
         name: "WebEngineFavicon"
+        when: windowShown
 
         function init() {
             if (webEngineView.icon != '') {
@@ -185,7 +190,7 @@ TestWebEngineView {
             iconChangedSpy.wait()
             compare(iconChangedSpy.count, 1)
 
-            iconUrl = webEngineView.icon
+            iconUrl = removeFaviconProviderPrefix(webEngineView.icon)
             // Touch icon is ignored
             compare(iconUrl, Qt.resolvedUrl("icons/qt32.ico"))
             compare(favicon.width, 32)
@@ -199,13 +204,13 @@ TestWebEngineView {
 
             iconChangedSpy.wait()
             verify(iconChangedSpy.count >= 1)
-            iconUrl = webEngineView.icon
+            iconUrl = removeFaviconProviderPrefix(webEngineView.icon)
 
             // If the icon URL is empty we have to wait for
             // the second iconChanged signal that propagates the expected URL
             if (iconUrl == Qt.resolvedUrl("")) {
                 tryCompare(iconChangedSpy, "count", 2)
-                iconUrl = webEngineView.icon
+                iconUrl = removeFaviconProviderPrefix(webEngineView.icon)
             }
 
             compare(iconUrl, Qt.resolvedUrl("icons/qt144.png"))
@@ -224,6 +229,21 @@ TestWebEngineView {
 
             var iconUrl = webEngineView.icon
             compare(iconUrl, Qt.resolvedUrl(""))
+            compare(favicon.width, 0)
+            compare(favicon.height, 0)
+
+            WebEngine.settings.touchIconsEnabled = true
+
+            url = Qt.resolvedUrl("favicon-touch.html")
+            webEngineView.url = url
+            verify(webEngineView.waitForLoadSucceeded())
+
+            iconChangedSpy.wait()
+            iconUrl = removeFaviconProviderPrefix(webEngineView.icon)
+            compare(iconUrl, Qt.resolvedUrl("icons/qt144.png"))
+            compare(iconChangedSpy.count, 1)
+            compare(favicon.width, 144)
+            compare(favicon.height, 144)
         }
 
         function test_multiIcon() {
@@ -235,11 +255,69 @@ TestWebEngineView {
 
             iconChangedSpy.wait()
             compare(iconChangedSpy.count, 1)
+            compare(favicon.width, 64)
+            compare(favicon.height, 64)
+        }
 
-            // Image QML type does not support multi-sized icons thus
-            // chooses the first size
-            compare(favicon.width, 16)
-            compare(favicon.height, 16)
+        function test_faviconProvider_data() {
+            return [
+                   { tag: "8x8", size: 8, value: 16 },
+                   { tag: "16x16", size: 16, value: 16 },
+                   { tag: "17x17", size: 17, value: 32 },
+                   { tag: "31x31", size: 31, value: 32 },
+                   { tag: "32x32", size: 32, value: 32 },
+                   { tag: "33x33", size: 33, value: 64 },
+                   { tag: "64x64", size: 64, value: 64 },
+                   { tag: "128x128", size: 128, value: 128 },
+                   { tag: "255x255", size: 255, value: 255 },
+                   { tag: "256x256", size: 256, value: 255 },
+            ];
+        }
+
+        function test_faviconProvider(row) {
+            var faviconImage = Qt.createQmlObject("
+                    import QtQuick 2.5\n
+                    Image { sourceSize: Qt.size(width, height) }", test)
+            var grabImage = Qt.createQmlObject("
+                    import QtQuick 2.5\n
+                    Image { }", test)
+            var faviconCanvas = Qt.createQmlObject("
+                    import QtQuick 2.5\n
+                    Canvas { }", test)
+
+            compare(iconChangedSpy.count, 0)
+
+            var url = Qt.resolvedUrl("favicon-multi-gray.html")
+            webEngineView.url = url
+            verify(webEngineView.waitForLoadSucceeded())
+
+            iconChangedSpy.wait()
+            compare(iconChangedSpy.count, 1)
+
+            faviconImage.width = row.size
+            faviconImage.height = row.size
+            faviconImage.source = webEngineView.icon
+            verify(_waitFor(function() { return faviconImage.status == Image.Ready } ))
+
+            faviconImage.grabToImage(function(result) {
+                    grabImage.source = result.url
+                })
+            verify(_waitFor(function() { return grabImage.status == Image.Ready } ))
+
+            faviconCanvas.width = faviconImage.width
+            faviconCanvas.height = faviconImage.height
+            var ctx = faviconCanvas.getContext("2d")
+            ctx.drawImage(grabImage, 0, 0, grabImage.width, grabImage.height)
+
+            var center = Math.round(row.size/2)
+            var imageData = ctx.getImageData(center, center, center, center)
+            var pixel = imageData.data
+
+            compare(pixel[0], row.value)
+
+            faviconImage.destroy()
+            grabImage.destroy()
+            faviconCanvas.destroy()
         }
     }
 }
diff --git a/tests/auto/quick/qmltests/data/tst_faviconDownload.qml b/tests/auto/quick/qmltests/data/tst_faviconDownload.qml
index e4dfb36aa..406dfa3ea 100644
--- a/tests/auto/quick/qmltests/data/tst_faviconDownload.qml
+++ b/tests/auto/quick/qmltests/data/tst_faviconDownload.qml
@@ -35,6 +35,10 @@ TestWebEngineView {
     width: 200
     height: 400
 
+    function removeFaviconProviderPrefix(url) {
+        return url.toString().substring(16)
+    }
+
     SignalSpy {
         id: iconChangedSpy
         target: webEngineView
@@ -108,7 +112,7 @@ TestWebEngineView {
             iconChangedSpy.wait()
             compare(iconChangedSpy.count, 1)
 
-            var iconUrl = webEngineView.icon
+            var iconUrl = removeFaviconProviderPrefix(webEngineView.icon)
             compare(iconUrl, row.expectedIconUrl)
         }
     }
diff --git a/tests/auto/quick/qmltests/qmltests.pro b/tests/auto/quick/qmltests/qmltests.pro
index 257c1c4f6..af6e14c33 100644
--- a/tests/auto/quick/qmltests/qmltests.pro
+++ b/tests/auto/quick/qmltests/qmltests.pro
@@ -18,6 +18,7 @@ OTHER_FILES += \
     $$PWD/data/favicon2.html \
     $$PWD/data/favicon-misc.html \
     $$PWD/data/favicon-multi.html \
+    $$PWD/data/favicon-multi-gray.html \
     $$PWD/data/favicon-single.html \
     $$PWD/data/favicon-shortcut.html \
     $$PWD/data/favicon-touch.html \
@@ -62,6 +63,7 @@ OTHER_FILES += \
     $$PWD/data/tst_webchannel.qml \
     $$PWD/data/tst_keyboardModifierMapping.qml \
     $$PWD/data/icons/favicon.png \
+    $$PWD/data/icons/grayicons.ico \
     $$PWD/data/icons/small-favicon.png \
     $$PWD/data/icons/qt144.png \
     $$PWD/data/icons/qt32.ico \