Animated scroll shouldn't require main-frame for OOPIFs.

content/renderer/gpu/render_widget_compositor.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_RENDERER_GPU_RENDER_WIDGET_COMPOSITOR_H_
 #define CONTENT_RENDERER_GPU_RENDER_WIDGET_COMPOSITOR_H_
 
 #include <stdint.h>
 
 #include "base/callback.h"
@@ skipping 48 matching lines @@
   static std::unique_ptr<RenderWidgetCompositor> Create(
       RenderWidgetCompositorDelegate* delegate,
       CompositorDependencies* compositor_deps);
 
   ~RenderWidgetCompositor() override;
 
   static cc::LayerTreeSettings GenerateLayerTreeSettings(
       const base::CommandLine& cmd,
       CompositorDependencies* compositor_deps,
       float device_scale_factor,
+      bool is_for_subframe,
       const ScreenInfo& screen_info);
   static std::unique_ptr<cc::LayerTreeHost> CreateLayerTreeHost(
       cc::LayerTreeHostClient* client,
       cc::LayerTreeHostSingleThreadClient* single_thread_client,
       cc::MutatorHost* mutator_host,
       CompositorDependencies* deps,
       float device_scale_factor,
       const ScreenInfo& screen_info);
 
   void Initialize(std::unique_ptr<cc::LayerTreeHost> layer_tree_host,
@@ skipping 111 matching lines @@
   void RecordWheelAndTouchScrollingCount(bool has_scrolled_by_wheel,
                                          bool has_scrolled_by_touch) override;
   void RequestNewCompositorFrameSink() override;
   void DidInitializeCompositorFrameSink() override;
   void DidFailToInitializeCompositorFrameSink() override;
   void WillCommit() override;
   void DidCommit() override;
   void DidCommitAndDrawFrame() override;
   void DidReceiveCompositorFrameAck() override;
   void DidCompletePageScaleAnimation() override;
+  bool IsForSubframe() override;
 
   // cc::LayerTreeHostSingleThreadClient implementation.
   void RequestScheduleAnimation() override;
   void DidSubmitCompositorFrame() override;
   void DidLoseCompositorFrameSink() override;
 
   enum {
     COMPOSITOR_FRAME_SINK_RETRIES_BEFORE_FALLBACK = 4,
     MAX_COMPOSITOR_FRAME_SINK_RETRIES = 5,
   };
@@ skipping 26 matching lines @@
   blink::WebLayoutAndPaintAsyncCallback* layout_and_paint_async_callback_;
 
   cc::FrameSinkId frame_sink_id_;
 
   base::WeakPtrFactory<RenderWidgetCompositor> weak_factory_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_GPU_RENDER_WIDGET_COMPOSITOR_H_