Mac Overlays: Allow SolidColor and Tile quads to be candidates for overlays.

cc/output/overlay_strategy_sandwich.cc

Index: cc/output/overlay_strategy_sandwich.cc
diff --git a/cc/output/overlay_strategy_sandwich.cc b/cc/output/overlay_strategy_sandwich.cc
index 515afa5c820a2999a4bdaa28640b66fe1cb84949..4aaa63d811750baf7470b63941ee184887a94e87 100644
--- a/cc/output/overlay_strategy_sandwich.cc
+++ b/cc/output/overlay_strategy_sandwich.cc
@@ -45,10 +45,12 @@ bool OverlayStrategySandwich::Attempt(RenderPassList* render_passes,
   QuadList& quad_list = render_passes->back()->quad_list;
   for (auto it = quad_list.begin(); it != quad_list.end();) {
     OverlayCandidate candidate;
-    if (OverlayCandidate::FromDrawQuad(*it, &candidate))
+    if (OverlayCandidate::IsVideoQuad(*it) &&
+        OverlayCandidate::FromDrawQuad(*it, &candidate)) {
       it = TryOverlay(render_passes->back(), candidate_list, candidate, it);
-    else
+    } else {
       ++it;
+    }
   }
 
   return candidate_list->size() > 1;