Force use of and cache render surface.

cc/layers/render_surface_impl.cc

Index: cc/layers/render_surface_impl.cc
diff --git a/cc/layers/render_surface_impl.cc b/cc/layers/render_surface_impl.cc
index c61a56ff3bcb5113272c752f43e6021f2d4f0d1c..161742506234f9544e22df6af311a93d18dffc03 100644
--- a/cc/layers/render_surface_impl.cc
+++ b/cc/layers/render_surface_impl.cc
@@ -153,6 +153,10 @@ bool RenderSurfaceImpl::HasCopyRequest() const {
   return OwningEffectNode()->has_copy_request;
 }
 
+bool RenderSurfaceImpl::ForceRenderSurface() const {
+  return OwningEffectNode()->force_render_surface;
+}
+
 int RenderSurfaceImpl::TransformTreeIndex() const {
   return OwningEffectNode()->transform_id;
 }
@@ -206,7 +210,7 @@ gfx::Rect RenderSurfaceImpl::CalculateExpandedClipForFilters(
 }
 
 gfx::Rect RenderSurfaceImpl::CalculateClippedAccumulatedContentRect() {
-  if (HasCopyRequest() || !is_clipped())
+  if (ForceRenderSurface() || HasCopyRequest() || !is_clipped())
     return accumulated_content_rect();
 
   if (accumulated_content_rect().IsEmpty())
@@ -366,6 +370,7 @@ std::unique_ptr<RenderPass> RenderSurfaceImpl::CreateRenderPass() {
                draw_properties_.screen_space_transform);
   pass->filters = Filters();
   pass->background_filters = BackgroundFilters();
+  pass->force_render_surface = ForceRenderSurface();
   return pass;
 }