Fixed crash when QMediaObject is deleted before QMediaRecorder.

Change-Id: I8a1674b6f3d2b2c9ab888facff21f94af41b81de
Reviewed-on: http://codereview.qt.nokia.com/3544
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Michael Goddard <michael.goddard@nokia.com>

src/multimediakit/qmediarecorder.cpp

@@ -168,7 +168,12 @@ void QMediaRecorderPrivate::_q_error(int error, const QString &errorString)
 
 void QMediaRecorderPrivate::_q_serviceDestroyed()
 {
-    q_func()->setMediaObject(0);
+    mediaObject = 0;
+    control = 0;
+    formatControl = 0;
+    audioControl = 0;
+    videoControl = 0;
+    metaDataControl = 0;
 }
 
 void QMediaRecorderPrivate::_q_notify()

tests/auto/qmediarecorder/tst_qmediarecorder.cpp

@@ -165,6 +165,26 @@ void tst_QMediaRecorder::testNullControls()
     QCOMPARE(spy.count(), 0);
 }
 
+void tst_QMediaRecorder::testDeleteMediaObject()
+{
+    MockMediaRecorderControl *mock = new MockMediaRecorderControl(this);
+    MockMediaRecorderService *service = new MockMediaRecorderService(this, mock);
+    MockMediaObject *object = new MockMediaObject(this, service);
+    QMediaRecorder *capture = new QMediaRecorder(object);
+
+    QVERIFY(capture->mediaObject() == object);
+    QVERIFY(capture->isAvailable());
+
+    delete object;
+    delete service;
+    delete mock;
+
+    QVERIFY(capture->mediaObject() == 0);
+    QVERIFY(!capture->isAvailable());
+
+    delete capture;
+}
+
 void tst_QMediaRecorder::testError()
 {
     const QString errorString(QLatin1String("format error"));

tests/auto/qmediarecorder/tst_qmediarecorder.h

@@ -70,6 +70,7 @@ public slots:
 private slots:
     void testNullService();
     void testNullControls();
+    void testDeleteMediaObject();
     void testError();
     void testSink();
     void testRecord();