UMA metrics for use count of wheel and touch scrolls.

content/renderer/gpu/render_widget_compositor_unittest.cc

Index: content/renderer/gpu/render_widget_compositor_unittest.cc
diff --git a/content/renderer/gpu/render_widget_compositor_unittest.cc b/content/renderer/gpu/render_widget_compositor_unittest.cc
index 1ddc434dc7c3b4bdb030aa551d9f37e0fb5592ae..421940dff24b1f530c13e431d31258a40b3db7ff 100644
--- a/content/renderer/gpu/render_widget_compositor_unittest.cc
+++ b/content/renderer/gpu/render_widget_compositor_unittest.cc
@@ -42,6 +42,8 @@ class StubRenderWidgetCompositorDelegate
                            const gfx::Vector2dF& elastic_overscroll_delta,
                            float page_scale,
                            float top_controls_delta) override {}
+  void RecordWheelAndTouchScrollingCount(bool has_scrolled_by_wheel,
+                                         bool has_scrolled_by_touch) override {}
   void BeginMainFrame(double frame_time_sec) override {}
   std::unique_ptr<cc::CompositorFrameSink> CreateCompositorFrameSink(
       const cc::FrameSinkId& frame_sink_id,