Adding hooks for gathering total pixels painted and rasterized stats.

cc/content_layer_updater.cc

Index: cc/content_layer_updater.cc
diff --git a/cc/content_layer_updater.cc b/cc/content_layer_updater.cc
index b151bfb34736822ca8d28e134fc3569216e7eb34..049261bde7ee00e6c0303d41ed8a674cfe9325f3 100644
--- a/cc/content_layer_updater.cc
+++ b/cc/content_layer_updater.cc
@@ -56,6 +56,8 @@ void ContentLayerUpdater::paintContents(SkCanvas* canvas, const IntRect& content
     stats.totalPaintTimeInSeconds += (base::TimeTicks::Now() - paintBeginTime).InSecondsF();
     canvas->restore();
 
+    stats.totalPixelsPainted += contentRect.width() * contentRect.height();
+
     FloatRect opaqueContentRect = opaqueLayerRect;
     opaqueContentRect.scale(contentsWidthScale, contentsHeightScale);
     resultingOpaqueRect = enclosedIntRect(opaqueContentRect);