Move middle-click autoscroll to synthetic fling.

content/renderer/render_widget.h

 // Copyright (c) 2012 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_RENDER_WIDGET_H_
 #define CONTENT_RENDERER_RENDER_WIDGET_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 267 matching lines @@
   void SetScreenMetricsEmulationParameters(
       bool enabled,
       const blink::WebDeviceEmulationParams& params) override;
   void SetScreenRects(const gfx::Rect& view_screen_rect,
                       const gfx::Rect& window_screen_rect) override;
 
   // blink::WebWidgetClient
   blink::WebLayerTreeView* InitializeLayerTreeView() override;
   void DidMeaningfulLayout(blink::WebMeaningfulLayout layout_type) override;
   void DidChangeCursor(const blink::WebCursorInfo&) override;
+  void AutoscrollStart(const blink::WebFloatPoint& point) override;
+  void AutoscrollFling(const blink::WebFloatSize& velocity) override;
+  void AutoscrollEnd() override;
   void CloseWidgetSoon() override;
   void Show(blink::WebNavigationPolicy) override;
   blink::WebRect WindowRect() override;
   blink::WebRect ViewRect() override;
   void SetToolTipText(const blink::WebString& text,
                       blink::WebTextDirection hint) override;
   void SetWindowRect(const blink::WebRect&) override;
   blink::WebScreenInfo GetScreenInfo() override;
   void DidHandleGestureEvent(const blink::WebGestureEvent& event,
                              bool event_cancelled) override;
@@ skipping 597 matching lines @@
   scoped_refptr<MainThreadEventQueue> input_event_queue_;
 
   base::WeakPtrFactory<RenderWidget> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidget);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_WIDGET_H_