Force use of and cache render surface.

components/viz/service/display/surface_aggregator.h

Index: components/viz/service/display/surface_aggregator.h
diff --git a/components/viz/service/display/surface_aggregator.h b/components/viz/service/display/surface_aggregator.h
index 55ef709bc92efc16472dfb89bbb3faa5fcad5e58..cc559208a0da4c97392acab9a44cac5f2608e5bb 100644
--- a/components/viz/service/display/surface_aggregator.h
+++ b/components/viz/service/display/surface_aggregator.h
@@ -200,6 +200,11 @@ class VIZ_SERVICE_EXPORT SurfaceAggregator {
   // should not have their damage rects clipped to the root damage rect.
   base::flat_set<cc::RenderPassId> copy_request_passes_;
 
+  // This is the set of aggregated pass ids that are drawn by force render
+  // surface, so should not have their damage rects clipped to the root damage
+  // rect.
+  base::flat_set<cc::RenderPassId> cached_render_surface_passes_;
+
   // This maps each aggregated pass id to the set of (aggregated) pass ids
   // that its RenderPassDrawQuads depend on
   base::flat_map<cc::RenderPassId, base::flat_set<cc::RenderPassId>>
@@ -212,6 +217,10 @@ class VIZ_SERVICE_EXPORT SurfaceAggregator {
   // This is valid during Aggregate after PrewalkTree is called.
   bool has_copy_requests_;
 
+  // True if the frame that's currently being aggregated has force render
+  // surface. This is valid during Aggregate after PrewalkTree is called.
+  bool has_cached_render_surfaces_;
+
   // Tracks UMA stats for SurfaceDrawQuads during a call to Aggregate().
   SurfaceDrawQuadUmaStats uma_stats_;