cc: Support mask layers in impl-side painting

cc/picture_layer.cc

Index: cc/picture_layer.cc
diff --git a/cc/picture_layer.cc b/cc/picture_layer.cc
index 241aff40dc3ca4eeaeb0db5e8d45d0f0cccaa2c3..d00f54b74e87e549a9d583bfe36cda9550f5c6cb 100644
--- a/cc/picture_layer.cc
+++ b/cc/picture_layer.cc
@@ -15,7 +15,8 @@ scoped_refptr<PictureLayer> PictureLayer::create(ContentLayerClient* client) {
 }
 
 PictureLayer::PictureLayer(ContentLayerClient* client) :
-  client_(client) {
+  client_(client),
+  is_mask_(false) {
 }
 
 PictureLayer::~PictureLayer() {
@@ -33,6 +34,7 @@ void PictureLayer::pushPropertiesTo(LayerImpl* base_layer) {
   Layer::pushPropertiesTo(base_layer);
 
   PictureLayerImpl* layer_impl = static_cast<PictureLayerImpl*>(base_layer);
+  layer_impl->SetIsMask(is_mask_);
   layer_impl->tilings_.SetLayerBounds(bounds());
   layer_impl->invalidation_.Clear();
   layer_impl->invalidation_.Swap(pile_invalidation_);
@@ -62,4 +64,8 @@ void PictureLayer::update(ResourceUpdateQueue&, const OcclusionTracker*,
   pile_.Update(client_, pile_invalidation_, stats);
 }
 
+void PictureLayer::setIsMask(bool is_mask) {
+  is_mask_ = is_mask;
+}
+
 }  // namespace cc