Force use of and cache render surface.

cc/quads/render_pass.h

Index: cc/quads/render_pass.h
diff --git a/cc/quads/render_pass.h b/cc/quads/render_pass.h
index 5a9910bc5fa503847b13604914dcdbfc72bd1c88..10c1996ab5ebe221c918bcbed1b22ed723f5ee36 100644
--- a/cc/quads/render_pass.h
+++ b/cc/quads/render_pass.h
@@ -87,7 +87,9 @@ class CC_EXPORT RenderPass {
               const FilterOperations& filters,
               const FilterOperations& background_filters,
               const gfx::ColorSpace& color_space,
-              bool has_transparent_background);
+              bool has_transparent_background,
+              bool cache_render_surface,
+              bool has_damage_from_contributing_content);
 
   void AsValueInto(base::trace_event::TracedValue* dict) const;
 
@@ -129,6 +131,12 @@ class CC_EXPORT RenderPass {
   // If false, the pixels in the render pass' texture are all opaque.
   bool has_transparent_background = true;
 
+  // If true we might reuse the texture if there is no damage.
+  bool cache_render_surface = false;
+  // A cumulated damage from contributing render surface or layer or surface

[vmpstr, 2017/07/13 18:01:03]

nit: Accumulated. Also, this comment isn't really saying what the bool holds.
Maybe say "Indicates whether there is accumulated damage ..."

[wutao, 2017/07/14 00:02:53]

Done.

+  // quad. Not including property changes on itself.
+  bool has_damage_from_contributing_content = false;
+
   // If non-empty, the renderer should produce a copy of the render pass'
   // contents as a bitmap, and give a copy of the bitmap to each callback in
   // this list. This property should not be serialized between compositors, as