[tracing] Add memory usage of Android UI resources to memory-infra

cc/resources/scoped_ui_resource.h

Index: cc/resources/scoped_ui_resource.h
diff --git a/cc/resources/scoped_ui_resource.h b/cc/resources/scoped_ui_resource.h
index 14db076b1e718dc705f426ad891139d3fab76cb1..58d5824f9d727ff274bba671ac0a488267e3561f 100644
--- a/cc/resources/scoped_ui_resource.h
+++ b/cc/resources/scoped_ui_resource.h
@@ -32,6 +32,9 @@ class CC_EXPORT ScopedUIResource : public UIResourceClient {
   UIResourceBitmap GetBitmap(UIResourceId uid, bool resource_lost) override;
   UIResourceId id() { return id_; }
 
+  // Returns the memory usage of the bitmap.
+  size_t BytesUsed() const { return bitmap_.BytesUsed(); }
+
  protected:
   ScopedUIResource(UIResourceManager* ui_resource_manager,
                    const UIResourceBitmap& bitmap);