Remove the last remainders of the old plugin system

Port the last two currently unused plugins (v4l and wmf) over to the new plugin
format.

Fix documentation that still mentioned Q_EXPORT_PLUGIN.

Change-Id: I18200dd792e8973687e92180fc41d11395b35132
Reviewed-by: Jonas Rabbe <jonas.rabbe@gmail.com>
Reviewed-by: Lars Knoll <lars.knoll@nokia.com>

src/plugins/wmf/wmf.json

@@ -0,0 +1,3 @@
+{
+    "Keys": ["org.qt-project.qt.mediaplayer"]
+}

src/plugins/wmf/wmfserviceplugin.cpp

@@ -49,15 +49,6 @@
 #endif
 #include <qmediaserviceprovider.h>
 
-QStringList WMFServicePlugin::keys() const
-{
-    return QStringList()
-#ifdef QMEDIA_MEDIAFOUNDATION_PLAYER
-            << QLatin1String(Q_MEDIASERVICE_MEDIAPLAYER)
-#endif
-            ;
-}
-
 QMediaService* WMFServicePlugin::create(QString const& key)
 {
 #ifdef QMEDIA_MEDIAFOUNDATION_PLAYER
@@ -93,5 +84,3 @@ QString WMFServicePlugin::deviceDescription(const QByteArray &service, const QBy
     return QString();
 }
 
-Q_EXPORT_PLUGIN2(qtmedia_wmfengine, WMFServicePlugin);
-

src/plugins/wmf/wmfserviceplugin.h

@@ -54,8 +54,8 @@ class WMFServicePlugin
     Q_OBJECT
     Q_INTERFACES(QMediaServiceSupportedDevicesInterface)
     Q_INTERFACES(QMediaServiceFeaturesInterface)
+    Q_PLUGIN_METADATA(IID "org.qt-project.qt.mediaserviceproviderfactory/5.0" FILE "wmf.json")
 public:
-    QStringList keys() const;
     QMediaService* create(QString const& key);
     void release(QMediaService *service);