Merge remote-tracking branch 'origin/5.11' into dev

 Conflicts:
	.qmake.conf

Change-Id: I8d0aa330c9e5b2031b40ca645356226e8ebb50c8

src/gsttools/qgstreamerbushelper.cpp

@@ -79,7 +79,11 @@ public:
         delete m_intervalTimer;
 
         if (m_tag)
+#if GST_CHECK_VERSION(1, 6, 0)
+            gst_bus_remove_watch(m_bus);
+#else
             g_source_remove(m_tag);
+#endif
     }
 
     GstBus* bus() const { return m_bus; }

src/multimedia/audio/qsamplecache_p.cpp

@@ -141,8 +141,10 @@ void QSampleCache::loadingRelease()
     m_loadingRefCount--;
     if (m_loadingRefCount == 0) {
         if (m_loadingThread.isRunning()) {
-            m_networkAccessManager->deleteLater();
-            m_networkAccessManager = nullptr;
+            if (m_networkAccessManager) {
+                m_networkAccessManager->deleteLater();
+                m_networkAccessManager = nullptr;
+            }
             m_loadingThread.exit();
         }
     }