Allow WebExternalTextureLayers to receive a bitmap along with a mailbox

cc/layers/texture_layer_client.h

Index: cc/layers/texture_layer_client.h
diff --git a/cc/layers/texture_layer_client.h b/cc/layers/texture_layer_client.h
index b5c0de61045086add6a5581d52f88c2b80c65608..b9fc51ca56573fe9af837794c7a4dc3f238f67f4 100644
--- a/cc/layers/texture_layer_client.h
+++ b/cc/layers/texture_layer_client.h
@@ -25,7 +25,8 @@ class TextureLayerClient {
   // Returns true and provides a mailbox if a new frame is available.
   // Returns false if no new data is available
   // and the old mailbox is to be reused.
-  virtual bool PrepareTextureMailbox(TextureMailbox* mailbox) = 0;
+  virtual bool PrepareTextureMailbox(TextureMailbox* mailbox,
+                                     bool use_shared_memory) = 0;
 
  protected:
   virtual ~TextureLayerClient() {}