Compute damage rect for Cast video compositing

cc/output/overlay_processor.cc

Index: cc/output/overlay_processor.cc
diff --git a/cc/output/overlay_processor.cc b/cc/output/overlay_processor.cc
index 88523d63033d86a45aa37d02c53e7f5e991364e0..cec4babb661bacc0ba02d62cda65c467706fa040 100644
--- a/cc/output/overlay_processor.cc
+++ b/cc/output/overlay_processor.cc
@@ -39,6 +39,10 @@ class SendPromotionHintsBeforeReturning {
 
 namespace cc {
 
+bool OverlayProcessor::Strategy::GetSwapWithDamageRect(gfx::Rect* rect) {
+  return false;
+}
+
 OverlayProcessor::OverlayProcessor(OutputSurface* surface) : surface_(surface) {
 }
 
@@ -88,6 +92,7 @@ void OverlayProcessor::ProcessForOverlays(ResourceProvider* resource_provider,
                                           OverlayCandidateList* candidates,
                                           CALayerOverlayList* ca_layer_overlays,
                                           gfx::Rect* damage_rect) {
+  have_swap_with_damage_rect_ = false;
 #if defined(OS_ANDROID)
   // Be sure to send out notifications, regardless of whether we get to
   // processing for overlays or not.  If we don't, then we should notify that
@@ -116,11 +121,20 @@ void OverlayProcessor::ProcessForOverlays(ResourceProvider* resource_provider,
     if (!strategy->Attempt(resource_provider, render_pass, candidates))
       continue;
 
+    have_swap_with_damage_rect_ =
+        strategy->GetSwapWithDamageRect(&swap_with_damage_rect_);
+
     UpdateDamageRect(candidates, damage_rect);
     return;
   }
 }
 
+bool OverlayProcessor::GetSwapWithDamageRect(gfx::Rect* damage_rect) {
+  DCHECK(damage_rect);
+  *damage_rect = swap_with_damage_rect_;
+  return have_swap_with_damage_rect_;
+}
+
 // Subtract on-top overlays from the damage rect, unless the overlays use
 // the backbuffer as their content (in which case, add their combined rect
 // back to the damage at the end).