AVFoundation: fix some controls not being correctly destroyed on iOS.

This patch also makes sure AVF video layers are removed from their
parent layer when their corresponding Qt video outputs are destroyed.

Task-number: QTBUG-39385
Change-Id: I164cd0da7084f84c0473ed3e396e734acce2a22e
Reviewed-by: Andy Nichols <andy.nichols@digia.com>

src/plugins/avfoundation/camera/avfcameraservice.mm

@@ -135,9 +135,9 @@ QMediaControl *AVFCameraService::requestControl(const char *name)
 void AVFCameraService::releaseControl(QMediaControl *control)
 {
     if (m_videoOutput == control) {
-        m_videoOutput = 0;
         m_session->setVideoOutput(0);
-        delete control;
+        delete m_videoOutput;
+        m_videoOutput = 0;
     }
 }
 

src/plugins/avfoundation/mediaplayer/avfmediaplayerservice.mm

@@ -118,14 +118,15 @@ void AVFMediaPlayerService::releaseControl(QMediaControl *control)
 #ifdef QT_DEBUG_AVF
     qDebug() << Q_FUNC_INFO << control;
 #endif
-#if defined(Q_OS_OSX)
     if (m_videoOutput == control) {
+#if defined(Q_OS_OSX)
         AVFVideoRendererControl *renderControl = qobject_cast<AVFVideoRendererControl*>(m_videoOutput);
         if (renderControl)
             renderControl->setSurface(0);
+#endif
         m_videoOutput = 0;
         m_session->setVideoOutput(0);
+
         delete control;
     }
-#endif
 }

src/plugins/avfoundation/mediaplayer/avfvideowidget.mm

@@ -64,8 +64,10 @@ AVFVideoWidget::~AVFVideoWidget()
     qDebug() << Q_FUNC_INFO;
 #endif
 
-    if (m_playerLayer)
+    if (m_playerLayer) {
+        [m_playerLayer removeFromSuperlayer];
         [m_playerLayer release];
+    }
 }
 
 QSize AVFVideoWidget::sizeHint() const

src/plugins/avfoundation/mediaplayer/avfvideowindowcontrol.mm

@@ -61,8 +61,10 @@ AVFVideoWindowControl::AVFVideoWindowControl(QObject *parent)
 
 AVFVideoWindowControl::~AVFVideoWindowControl()
 {
-    if (m_playerLayer)
+    if (m_playerLayer) {
+        [m_playerLayer removeFromSuperlayer];
         [m_playerLayer release];
+    }
 }
 
 WId AVFVideoWindowControl::winId() const