videomanager: follow API changes

Use return value of registerSinkTarget

Change-Id: Ibc7e8076a9446175d173b10aff18255893b1a8f7

src/libclient/directrenderer.cpp

@@ -39,7 +39,8 @@ public:
         , parent_(parent)
     {
         configureTarget();
-        VideoManager::instance().registerSinkTarget(parent_->id(), target);
+        if (!VideoManager::instance().registerSinkTarget(parent_->id(), target))
+            qWarning() << "Cannot register " << parent_->id();
     };
     ~Impl()
     {

src/libclient/qtwrapper/videomanager_wrap.h

@@ -141,13 +141,14 @@ public Q_SLOTS: // METHODS
 
     void stopAudioDevice() { DRing::stopAudioDevice(); }
 
-    void registerSinkTarget(const QString& sinkID, const DRing::SinkTarget& target)
+    bool registerSinkTarget(const QString& sinkID, const DRing::SinkTarget& target)
     {
 #ifdef ENABLE_VIDEO
-        DRing::registerSinkTarget(sinkID.toStdString(), target);
+        return DRing::registerSinkTarget(sinkID.toStdString(), target);
 #else
         Q_UNUSED(sinkID)
         Q_UNUSED(target)
+        return false;
 #endif
     }