Pass allow_delayed_resize in CompositorFrameMetadata

cc/output/compositor_frame_metadata.h

Index: cc/output/compositor_frame_metadata.h
diff --git a/cc/output/compositor_frame_metadata.h b/cc/output/compositor_frame_metadata.h
index 54c3ce61a0fae5e8c0dab07b5c30d5e2a9ad31c1..46c4ca4f23949bb0ee62ed997167e51f7dfe6496 100644
--- a/cc/output/compositor_frame_metadata.h
+++ b/cc/output/compositor_frame_metadata.h
@@ -40,6 +40,16 @@ class CC_EXPORT CompositorFrameMetadata {
   gfx::Vector2dF location_bar_content_translation;
   float overdraw_bottom_height;
 
+  // When showing or hiding top controls, the compositor calculates
+  // |viewport_size| according to the original viewport size and the position
+  // of the top controls. However, the viewport size of blink is only updated
+  // after the browser sends the resize event, causing inconsistency between
+  // the compositor and blink about the position of bottom-fixed-position
+  // elements. When such elements exist, the browser needs to send the resize
+  // event before sending any position-related events; otherwise it can delay
+  // the event if needed.
+  bool allow_delayed_resize;
+
   std::vector<ui::LatencyInfo> latency_info;
 };