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

cc/output/overlay_strategy_underlay.cc

Index: cc/output/overlay_strategy_underlay.cc
diff --git a/cc/output/overlay_strategy_underlay.cc b/cc/output/overlay_strategy_underlay.cc
index 805855cbcbec0646d3c3909c19244f3b60f5a9df..ad928731014ab0b8a69650c3f13cab81e1d99f24 100644
--- a/cc/output/overlay_strategy_underlay.cc
+++ b/cc/output/overlay_strategy_underlay.cc
@@ -23,7 +23,8 @@ bool OverlayStrategyUnderlay::Attempt(RenderPassList* render_passes,
   QuadList& quad_list = render_passes->back()->quad_list;
   for (auto it = quad_list.begin(); it != quad_list.end(); ++it) {
     OverlayCandidate candidate;
-    if (!OverlayCandidate::FromDrawQuad(*it, &candidate))
+    if (!OverlayCandidate::IsVideoQuad(*it) ||
+        !OverlayCandidate::FromDrawQuad(*it, &candidate))
       continue;
 
     // Add the overlay.