BUG: Fix bug leaking OpenGL resources when actors are removed.

Change-Id: Ib4697b9465d555d510d9ee835f3e907daadb4a06

GUISupport/Qt/QVTKGraphicsItem.cxx

@@ -59,6 +59,7 @@ void QVTKGraphicsItem::SetRenderWindow(vtkGenericOpenGLRenderWindow* win)
 {
   if(mWin)
   {
+    mWin->SetMapped(0);
     mConnect->Disconnect(mWin, vtkCommand::StartEvent, this, SLOT(Start()));
     mConnect->Disconnect(mWin, vtkCommand::WindowMakeCurrentEvent, this, SLOT(MakeCurrent()));
     mConnect->Disconnect(mWin, vtkCommand::EndEvent, this, SLOT(End()));
@@ -74,6 +75,7 @@ void QVTKGraphicsItem::SetRenderWindow(vtkGenericOpenGLRenderWindow* win)
 
   if(mWin)
   {
+    mWin->SetMapped(1);
     mWin->SetDoubleBuffer(0);
     mWin->SetFrontBuffer(vtkgl::COLOR_ATTACHMENT0_EXT);
     mWin->SetFrontLeftBuffer(vtkgl::COLOR_ATTACHMENT0_EXT);

GUISupport/Qt/QVTKWidget2.cxx

@@ -137,6 +137,7 @@ void QVTKWidget2::SetRenderWindow(vtkGenericOpenGLRenderWindow* w)
   if(this->mRenWin)
     {
     this->mRenWin->Finalize();
+    this->mRenWin->SetMapped(0);
     mConnect->Disconnect(mRenWin, vtkCommand::WindowMakeCurrentEvent, this, SLOT(MakeCurrent()));
     mConnect->Disconnect(mRenWin, vtkCommand::WindowIsCurrentEvent, this, SLOT(IsCurrent(vtkObject*, unsigned long, void*, void*)));
     mConnect->Disconnect(mRenWin, vtkCommand::WindowFrameEvent, this, SLOT(Frame()));
@@ -153,6 +154,7 @@ void QVTKWidget2::SetRenderWindow(vtkGenericOpenGLRenderWindow* w)
     {
     // if it is mapped somewhere else, unmap it
     this->mRenWin->Finalize();
+    this->mRenWin->SetMapped(1);
 
     // tell the vtk window what the size of this window is
     this->mRenWin->SetSize(this->width(), this->height());