Bug 595277 - Part 0: Clear out user data on destroy. r=roc

gfx/layers/Layers.h

@@ -190,6 +190,15 @@ public:
     return mKey == aKey ? mValue.get() : nsnull;
   }
 
+  /**
+   * Clear out current user data.
+   */
+  void Clear()
+  {
+    mKey = nsnull;
+    mValue = nsnull;
+  }
+
 private:
   void* mKey;
   nsAutoPtr<LayerUserData> mValue;
@@ -241,7 +250,7 @@ public:
    * for its widget going away.  After this call, only user data calls
    * are valid on the layer manager.
    */
-  virtual void Destroy() { mDestroyed = PR_TRUE; }
+  virtual void Destroy() { mDestroyed = PR_TRUE; mUserData.Clear(); }
   PRBool IsDestroyed() { return mDestroyed; }
 
   /**

widget/src/windows/nsWindow.cpp

@@ -3196,6 +3196,7 @@ nsWindow::GetLayerManager(bool* aAllowRetaining)
       if (layerManagerD3D10->device() !=
           gfxWindowsPlatform::GetPlatform()->GetD3D10Device())
       {
+        mLayerManager->Destroy();
         mLayerManager = nsnull;
       }
     }

widget/src/windows/nsWindowGfx.cpp

@@ -608,6 +608,7 @@ PRBool nsWindow::OnPaint(HDC aDC, PRUint32 aNestingLevel)
           layerManagerD3D9->SetClippingRegion(event.region);
           result = DispatchWindowEvent(&event, eventStatus);
           if (layerManagerD3D9->DeviceWasRemoved()) {
+            mLayerManager->Destroy();
             mLayerManager = nsnull;
             // When our device was removed, we should have gfxWindowsPlatform
             // check if its render mode is up to date!

widget/src/xpwidgets/PuppetWidget.cpp

@@ -154,6 +154,9 @@ PuppetWidget::Destroy()
   Base::Destroy();
   mPaintTask.Revoke();
   mChild = nsnull;
+  if (mLayerManager) {
+    mLayerManager->Destroy();
+  }
   mLayerManager = nsnull;
   mTabChild = nsnull;
   return NS_OK;

widget/src/xpwidgets/nsBaseWidget.cpp

@@ -137,6 +137,10 @@ nsBaseWidget::~nsBaseWidget()
     static_cast<BasicLayerManager*>(mLayerManager.get())->ClearRetainerWidget();
   }
 
+  if (mLayerManager) {
+    mLayerManager->Destroy();
+  }
+
 #ifdef NOISY_WIDGET_LEAKS
   gNumWidgets--;
   printf("WIDGETS- = %d\n", gNumWidgets);
@@ -1027,6 +1031,9 @@ nsBaseWidget::SetAcceleratedRendering(PRBool aEnabled)
     return NS_OK;
   }
   mUseAcceleratedRendering = aEnabled;
+  if (mLayerManager) {
+    mLayerManager->Destroy();
+  }
   mLayerManager = NULL;
   return NS_OK;
 }