Bug 832508 - When resuming Fennec and re-recreating the surface, force a first-paint notification from the compositor. r=Cwiiis

gfx/layers/ipc/CompositorParent.h

@@ -75,6 +75,14 @@ public:
   virtual void ShadowLayersUpdated(ShadowLayersParent* aLayerTree,
                                    const TargetConfig& aTargetConfig,
                                    bool isFirstPaint) MOZ_OVERRIDE;
+  /**
+   * This forces the is-first-paint flag to true. This is intended to
+   * be called by the widget code when it loses its viewport information
+   * (or for whatever reason wants to refresh the viewport information).
+   * The information refresh happens because the compositor will call
+   * SetFirstPaintViewport on the next frame of composition.
+   */
+  void ForceIsFirstPaint() { mIsFirstPaint = true; }
   void Destroy();
 
   LayerManager* GetLayerManager() { return mLayerManager; }

widget/android/AndroidBridge.cpp

@@ -1110,6 +1110,12 @@ AndroidBridge::SetLayerClient(JNIEnv* env, jobject jobj)
 
     if (resetting) {
         RegisterCompositor(env, true);
+#ifdef MOZ_ANDROID_OMTC
+        // since we are re-linking the new java objects to Gecko, we need to get
+        // the viewport from the compositor (since the Java copy was thrown away)
+        // and we do that by setting the first-paint flag.
+        nsWindow::ForceIsFirstPaint();
+#endif
     }
 }
 

widget/android/nsWindow.cpp

@@ -2330,6 +2330,14 @@ nsWindow::ScheduleResumeComposition(int width, int height)
     }
 }
 
+void
+nsWindow::ForceIsFirstPaint()
+{
+    if (sCompositorParent) {
+        sCompositorParent->ForceIsFirstPaint();
+    }
+}
+
 float
 nsWindow::ComputeRenderIntegrity()
 {

widget/android/nsWindow.h

@@ -156,6 +156,7 @@ public:
     static void ScheduleComposite();
     static void SchedulePauseComposition();
     static void ScheduleResumeComposition(int width, int height);
+    static void ForceIsFirstPaint();
     static float ComputeRenderIntegrity();
 
     virtual bool WidgetPaintsBackground();