cc: Avoid redraw for missing tile outside visible rect

cc/layers/append_quads_data.h

Index: cc/layers/append_quads_data.h
diff --git a/cc/layers/append_quads_data.h b/cc/layers/append_quads_data.h
index 6326bbb8ab64e59feb15a4108116ccb274431f2e..8e0fbef803b35b49b655be7f9188cfbbd4d18dd4 100644
--- a/cc/layers/append_quads_data.h
+++ b/cc/layers/append_quads_data.h
@@ -13,22 +13,30 @@ namespace cc {
 struct AppendQuadsData {
   AppendQuadsData()
       : num_incomplete_tiles(0),
+        num_incomplete_tiles_inside_activation_rect(0),
         num_missing_tiles(0),
+        num_missing_tiles_inside_activation_rect(0),
         visible_content_area(0),
         approximated_visible_content_area(0),
         render_pass_id(0, 0) {}
 
   explicit AppendQuadsData(RenderPass::Id render_pass_id)
       : num_incomplete_tiles(0),
+        num_incomplete_tiles_inside_activation_rect(0),
         num_missing_tiles(0),
+        num_missing_tiles_inside_activation_rect(0),
         visible_content_area(0),
         approximated_visible_content_area(0),
         render_pass_id(render_pass_id) {}
 
   // Set by the layer appending quads.
   int64 num_incomplete_tiles;
+  // Set by the layer appending quads. Subset of |num_incomplete_tiles|.
+  int64 num_incomplete_tiles_inside_activation_rect;
   // Set by the layer appending quads.
   int64 num_missing_tiles;
+  // Set by the layer appending quads. Subset of |num_missing_tiles|.
+  int64 num_missing_tiles_inside_activation_rect;
   // Set by the layer appending quads.
   int64 visible_content_area;
   // Set by the layer appending quads.