cc: Optimize decode scheduling for checker-images.

cc/tiles/tile_draw_info.h

Index: cc/tiles/tile_draw_info.h
diff --git a/cc/tiles/tile_draw_info.h b/cc/tiles/tile_draw_info.h
index 8ba08857dd22b5ac3113473320828598990e544c..2f5478bc1d051e48011225c9bd1ae0f450e11ea8 100644
--- a/cc/tiles/tile_draw_info.h
+++ b/cc/tiles/tile_draw_info.h
@@ -77,6 +77,10 @@ class CC_EXPORT TileDrawInfo {
     return resource_ ? IsResourceFormatCompressed(resource_->format()) : false;
   }
 
+  bool is_checker_imaged() const {

[vmpstr, 2017/03/29 19:11:45]

Just by looking at tile.h and tile_draw_info.h, the two flags you're adding seem
to say very similar things, so I think you need to add a comment explaining the
state. 

[Khushal, 2017/03/31 04:31:00]

Done.

+    return has_resource() && resource_is_checker_imaged_;
+  }
+
   void SetSolidColorForTesting(SkColor color) { set_solid_color(color); }
 
   void AsValueInto(base::trace_event::TracedValue* state) const;
@@ -90,6 +94,7 @@ class CC_EXPORT TileDrawInfo {
   void set_resource(Resource* resource) {
     mode_ = RESOURCE_MODE;
     is_resource_ready_to_draw_ = false;
+    resource_is_checker_imaged_ = false;

[vmpstr, 2017/03/29 19:11:45]

What if we set a resource that _is_ checker imaged?

Can you make this more robust in terms of order of operations?

That is
info.resource_is_checker_imaged_ = true;
info.set_resource(resource); 

will seem to do the wrong thing here.

Maybe add a bool to set_resource indicating whether the resource was checker
imaged with a default value of false?

[Khushal, 2017/03/29 22:10:20]

That makes sense.

[Khushal, 2017/03/31 04:31:00]

Done.

     resource_ = resource;
   }
 
@@ -109,6 +114,7 @@ class CC_EXPORT TileDrawInfo {
   Mode mode_ = RESOURCE_MODE;
   SkColor solid_color_ = SK_ColorWHITE;
   Resource* resource_ = nullptr;
+  bool resource_is_checker_imaged_ = false;

[vmpstr, 2017/03/29 19:11:45]

I'm not really a fan of "checker_imaged" as a name. I don't really have better
suggestions, but maybe you can come up with something.

[Khushal, 2017/03/29 22:10:20]

At this point, may be just keep that for consistency? Coz everything else in the
system is called checker-imaged...

   bool contents_swizzled_ = false;
   bool is_resource_ready_to_draw_ = false;
 };