cc: ReadyToDraw notifications.

cc/resources/tile.h

Index: cc/resources/tile.h
diff --git a/cc/resources/tile.h b/cc/resources/tile.h
index a712a754e40250ebd999105e182ec1980f10de30..e5f228e992531d50c25c375aab58f128e31d36cc 100644
--- a/cc/resources/tile.h
+++ b/cc/resources/tile.h
@@ -89,6 +89,10 @@ class CC_EXPORT Tile : public RefCountedManaged<Tile> {
   void set_required_for_activation(bool is_required) {
     required_for_activation_ = is_required;
   }
+  bool required_for_draw() const { return required_for_draw_; }
+  void set_required_for_draw(bool is_required) {
+    required_for_draw_ = is_required;
+  }
 
   bool use_picture_analysis() const {
     return !!(flags_ & USE_PICTURE_ANALYSIS);
@@ -178,6 +182,7 @@ class CC_EXPORT Tile : public RefCountedManaged<Tile> {
   int tiling_i_index_;
   int tiling_j_index_;
   bool required_for_activation_;
+  bool required_for_draw_;
 
   Id id_;
   static Id s_next_id_;