Delay activation/draw on GPU tile work completion

cc/raster/bitmap_raster_buffer_provider.h

Index: cc/raster/bitmap_raster_buffer_provider.h
diff --git a/cc/raster/bitmap_raster_buffer_provider.h b/cc/raster/bitmap_raster_buffer_provider.h
index ded16f5f76af1238277c58523e3830659778fcc3..58815650c4de23e1deee0841dedd937b44c731fe 100644
--- a/cc/raster/bitmap_raster_buffer_provider.h
+++ b/cc/raster/bitmap_raster_buffer_provider.h
@@ -37,6 +37,10 @@ class CC_EXPORT BitmapRasterBufferProvider : public RasterBufferProvider {
   ResourceFormat GetResourceFormat(bool must_support_alpha) const override;
   bool IsResourceSwizzleRequired(bool must_support_alpha) const override;
   bool CanPartialRasterIntoProvidedResource() const override;
+  uint64_t SetReadyToDrawCallback(
+      const ResourceProvider::ResourceIdArray& resource_ids,
+      const base::Callback<void(uint64_t)>& callback,
+      uint64_t pending_callback_id) const override;
   void Shutdown() override;
 
  protected: