cc: Distinguish single texture mask from normal masks

cc/layers/picture_layer.cc

Index: cc/layers/picture_layer.cc
diff --git a/cc/layers/picture_layer.cc b/cc/layers/picture_layer.cc
index ca425afa286214e72222a29976196b0f6d98c75c..a8c240ffb29d6a9b9c225f09eed94885f72e3ce2 100644
--- a/cc/layers/picture_layer.cc
+++ b/cc/layers/picture_layer.cc
@@ -27,7 +27,8 @@ scoped_refptr<PictureLayer> PictureLayer::Create(ContentLayerClient* client) {
 PictureLayer::PictureLayer(ContentLayerClient* client)
     : instrumentation_object_tracker_(id()),
       update_source_frame_number_(-1),
-      is_mask_(false) {
+      is_mask_(false),
+      is_single_texture_mask_(false) {
   picture_layer_inputs_.client = client;
 }
 
@@ -42,7 +43,8 @@ PictureLayer::~PictureLayer() {
 
 std::unique_ptr<LayerImpl> PictureLayer::CreateLayerImpl(
     LayerTreeImpl* tree_impl) {
-  return PictureLayerImpl::Create(tree_impl, id(), is_mask_);
+  return PictureLayerImpl::Create(tree_impl, id(), is_mask_,
+                                  is_single_texture_mask_);
 }
 
 void PictureLayer::PushPropertiesTo(LayerImpl* base_layer) {
@@ -51,6 +53,7 @@ void PictureLayer::PushPropertiesTo(LayerImpl* base_layer) {
   PictureLayerImpl* layer_impl = static_cast<PictureLayerImpl*>(base_layer);
   // TODO(danakj): Make is_mask_ a constructor parameter for PictureLayer.
   DCHECK_EQ(layer_impl->is_mask(), is_mask_);
+  DCHECK_EQ(layer_impl->is_single_texture_mask(), is_single_texture_mask_);
   DropRecordingSourceContentIfInvalid();
 
   layer_impl->SetNearestNeighbor(picture_layer_inputs_.nearest_neighbor);
@@ -141,6 +144,10 @@ void PictureLayer::SetIsMask(bool is_mask) {
   is_mask_ = is_mask;
 }
 
+void PictureLayer::SetIsSingleTextureMask(bool is_single_texture_mask) {
+  is_single_texture_mask_ = is_single_texture_mask;
+}
+
 sk_sp<SkPicture> PictureLayer::GetPicture() const {
   // We could either flatten the RecordingSource into a single SkPicture, or
   // paint a fresh one depending on what we intend to do with it.  For now we