Bug 1231564 - Don't trigger new composites just to repaint debug overlays. r=BenWa

gfx/layers/composite/LayerManagerComposite.cpp

@@ -430,7 +430,7 @@ LayerManagerComposite::UpdateAndRender()
 
   // We don't want our debug overlay to cause more frames to happen
   // so we will invalidate after we've decided if something changed.
-  InvalidateDebugOverlay(mRenderBounds);
+  InvalidateDebugOverlay(invalid, mRenderBounds);
 
   if (!didEffectiveTransforms) {
     // The results of our drawing always go directly into a pixel buffer,
@@ -521,23 +521,18 @@ LayerManagerComposite::RootLayer() const
 #endif
 
 void
-LayerManagerComposite::InvalidateDebugOverlay(const IntRect& aBounds)
+LayerManagerComposite::InvalidateDebugOverlay(nsIntRegion& aInvalidRegion, const IntRect& aBounds)
 {
   bool drawFps = gfxPrefs::LayersDrawFPS();
   bool drawFrameCounter = gfxPrefs::DrawFrameCounter();
   bool drawFrameColorBars = gfxPrefs::CompositorDrawColorBars();
 
   if (drawFps || drawFrameCounter) {
-    AddInvalidRegion(nsIntRect(0, 0, 256, 256));
+    aInvalidRegion.Or(aInvalidRegion, nsIntRect(0, 0, 256, 256));
   }
   if (drawFrameColorBars) {
-    AddInvalidRegion(nsIntRect(0, 0, 10, aBounds.height));
+    aInvalidRegion.Or(aInvalidRegion, nsIntRect(0, 0, 10, aBounds.height));
   }
-
-  if (drawFrameColorBars) {
-    AddInvalidRegion(nsIntRect(0, 0, 10, aBounds.height));
-  }
-
 }
 
 static uint16_t sFrameCount = 0;

gfx/layers/composite/LayerManagerComposite.h

@@ -328,7 +328,7 @@ private:
   /**
    * We need to know our invalid region before we're ready to render.
    */
-  void InvalidateDebugOverlay(const gfx::IntRect& aBounds);
+  void InvalidateDebugOverlay(nsIntRegion& aInvalidRegion, const gfx::IntRect& aBounds);
 
   /**
    * Render debug overlays such as the FPS/FrameCounter above the frame.