Add hints for potential overlay promotion on android.

cc/resources/texture_mailbox.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_RESOURCES_TEXTURE_MAILBOX_H_
 #define CC_RESOURCES_TEXTURE_MAILBOX_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 56 matching lines @@
   void set_color_space(const gfx::ColorSpace& color_space) {
     color_space_ = color_space;
   }
 
   // This is valid if allow_overlau() or IsSharedMemory() is true.
   gfx::Size size_in_pixels() const { return size_in_pixels_; }
 
   SharedBitmap* shared_bitmap() const { return shared_bitmap_; }
   size_t SharedMemorySizeInBytes() const;
 
+#if defined(OS_ANDROID)
+  bool is_backed_by_surface_texture() const {
+    return is_backed_by_surface_texture_;
+  }
+
+  void set_is_backed_by_surface_texture(bool value) {
+    is_backed_by_surface_texture_ = value;
+  }
+#endif
+
  private:
   gpu::MailboxHolder mailbox_holder_;
   SharedBitmap* shared_bitmap_;
   gfx::Size size_in_pixels_;
   bool is_overlay_candidate_;
+#if defined(OS_ANDROID)
+  bool is_backed_by_surface_texture_;
+#endif
   bool secure_output_only_;
   bool nearest_neighbor_;
   gfx::ColorSpace color_space_;
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_TEXTURE_MAILBOX_H_