UMA metrics for use count of wheel and touch scrolls.

content/renderer/gpu/render_widget_compositor_delegate.h

 // Copyright 2015 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_DELEGATE_H_
 #define CONTENT_RENDERER_GPU_RENDER_WIDGET_COMPOSITOR_DELEGATE_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 18 matching lines @@
  public:
   // Report viewport related properties during a commit from the compositor
   // thread.
   virtual void ApplyViewportDeltas(
       const gfx::Vector2dF& inner_delta,
       const gfx::Vector2dF& outer_delta,
       const gfx::Vector2dF& elastic_overscroll_delta,
       float page_scale,
       float top_controls_delta) = 0;
 
+  // Record use count of wheel/touch sources for scrolling on the compositor
+  // tread.

[danakj, 2017/03/16 15:19:21]

thread

[sahel, 2017/03/17 21:02:34]

Done.

+  virtual void RecordWheelAndTouchScrollingCount(
+      bool has_scrolled_by_wheel,
+      bool has_scrolled_by_touch) = 0;
+
   // Notifies that the compositor has issed a BeginMainFrame.
   virtual void BeginMainFrame(double frame_time_sec) = 0;
 
   // Requests a CompositorFrameSink to submit to.
   virtual std::unique_ptr<cc::CompositorFrameSink> CreateCompositorFrameSink(
       const cc::FrameSinkId& frame_sink_id,
       bool fallback) = 0;
 
   // Notifies that the draw commands for a committed frame have been issued.
   virtual void DidCommitAndDrawCompositorFrame() = 0;
@@ skipping 29 matching lines @@
   virtual std::unique_ptr<cc::SwapPromise> RequestCopyOfOutputForLayoutTest(
       std::unique_ptr<cc::CopyOutputRequest> request) = 0;
 
  protected:
   virtual ~RenderWidgetCompositorDelegate() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_GPU_RENDER_WIDGET_COMPOSITOR_DELEGATE_H_