Force use of and cache render surface.

cc/layers/layer.h

Index: cc/layers/layer.h
diff --git a/cc/layers/layer.h b/cc/layers/layer.h
index b63ad10e0a07287aaa7e16c241d71e6a7ededa96..64b29572f5857701f76f571dc380fe0fa767739c 100644
--- a/cc/layers/layer.h
+++ b/cc/layers/layer.h
@@ -259,6 +259,9 @@ class CC_EXPORT Layer : public base::RefCounted<Layer> {
     inputs_.did_scroll_callback = std::move(callback);
   }
 
+  void SetCacheRenderSurface(bool cache_render_surface);
+  bool cache_render_surface() const { return cache_render_surface_; }
+
   void SetForceRenderSurfaceForTesting(bool force_render_surface);
   bool force_render_surface_for_testing() const {
     return force_render_surface_for_testing_;
@@ -627,6 +630,8 @@ class CC_EXPORT Layer : public base::RefCounted<Layer> {
   bool should_flatten_transform_from_property_tree_ : 1;
   bool draws_content_ : 1;
   bool should_check_backface_visibility_ : 1;
+  // Force use of and cache render surface.
+  bool cache_render_surface_ : 1;
   bool force_render_surface_for_testing_ : 1;
   bool subtree_property_changed_ : 1;
   bool may_contain_video_ : 1;