Adding hasAudio and hasVideo properties to QML MediaPlayer

Adding hasAudio and hasVideo to MediaPlayer QML object to allow users
to determine whether the current media has audio and/or video
streams. Also adding notifies for when these properties change.

Change-Id: Ife7606e148f0c0ad558b4019c68c70973c199c08
Reviewed-by: Sergey Dubitskiy
Reviewed-by: Michael Goddard <michael.goddard@nokia.com>

src/imports/multimedia/qdeclarativeaudio.cpp

@@ -260,6 +260,28 @@ QDeclarativeAudio::Status QDeclarativeAudio::status() const
     This property holds whether the audio output is muted.
 */
 
+/*!
+    \qmlproperty bool Audio::hasAudio
+
+    This property holds whether the media contains audio.
+*/
+
+bool QDeclarativeAudio::hasAudio() const
+{
+    return !m_complete ? false : m_playerControl->isAudioAvailable();
+}
+
+/*!
+    \qmlproperty bool Audio::hasVideo
+
+    This property holds whether the media contains video.
+*/
+
+bool QDeclarativeAudio::hasVideo() const
+{
+    return !m_complete ? false : m_playerControl->isVideoAvailable();
+}
+
 /*!
     \qmlproperty real Audio::bufferProgress
 
@@ -305,6 +327,14 @@ QDeclarativeAudio::Error QDeclarativeAudio::error() const
 void QDeclarativeAudio::classBegin()
 {
     setObject(this);
+
+    if (m_mediaService) {
+        connect(m_playerControl, SIGNAL(audioAvailableChanged(bool)),
+                this, SIGNAL(hasAudioChanged()));
+        connect(m_playerControl, SIGNAL(videoAvailableChanged(bool)),
+                this, SIGNAL(hasVideoChanged()));
+    }
+
     emit mediaObjectChanged();
 }