phase based wheel scroll latching for mac

content/browser/renderer_host/render_widget_host_view_mac.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_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_
 
 #import <Cocoa/Cocoa.h>
 #include <IOSurface/IOSurface.h>
 #include <stddef.h>
@@ skipping 469 matching lines @@
 
   // Returns the TextSelection information for the active widget. If
   // |is_guest_view_hack_| is true, then it will return the TextSelection
   // information for this RenderWidgetHostViewMac (which is serving as a
   // platform view for a guest).
   const TextInputManager::TextSelection* GetTextSelection();
 
   // Get the focused view that should be used for retrieving the text selection.
   RenderWidgetHostViewBase* GetFocusedViewForTextSelection();
 
+  void ScheduleMouseWheelEndDispatching(blink::WebMouseWheelEvent wheel_event,
+                                        bool should_route_event);
+  void DispatchPendingWheelEndEvent();
+  void IgnorePendingWheelEndEvent();
+  bool HasPendingWheelEndEvent();
+
   // Returns the RenderWidgetHostDelegate corresponding to the currently focused
   // RenderWidgetHost. It is different from |render_widget_host_->delegate()|
   // when there are focused inner WebContentses on the page. Also, this method
   // can return nullptr; for instance when |render_widget_host_| becomes nullptr
   // in the destruction path of the WebContentsImpl.
   RenderWidgetHostDelegate* GetFocusedRenderWidgetHostDelegate();
 
  private:
   friend class RenderWidgetHostViewMacTest;
 
   // Returns whether this render view is a popup (autocomplete window).
   bool IsPopup() const;
 
   // Shuts down the render_widget_host_.  This is a separate function so we can
   // invoke it from the message loop.
   void ShutdownHost();
 
   // IPC message handlers.
   void OnGetRenderedTextCompleted(const std::string& text);
 
   // Send updated vsync parameters to the top level display.
   void UpdateDisplayVSyncParameters();
 
   // Dispatches a TTS session.
   void SpeakText(const std::string& text);
 
   // Adds/Removes frame observer based on state.
   void UpdateNeedsBeginFramesInternal();
 
+  void SendSyntheticWheelEventWithPhaseEnded(
+      blink::WebMouseWheelEvent wheel_event,
+      bool should_route_event);
+
   // The associated view. This is weak and is inserted into the view hierarchy
   // to own this RenderWidgetHostViewMac object. Set to nil at the start of the
   // destructor.
   RenderWidgetHostViewCocoa* cocoa_view_;
 
   // Indicates if the page is loading.
   bool is_loading_;
 
   // Whether it's allowed to pause waiting for a new frame.
   bool allow_pause_for_resize_or_repaint_;
@@ skipping 29 matching lines @@
   bool needs_begin_frames_;
 
   // Whether a request to flush input has been issued.
   bool needs_flush_input_;
 
   // The background color of the web content. This color will be drawn when the
   // web content is not able to draw in time.
   SkColor background_color_ = SK_ColorTRANSPARENT;
   SkColor last_frame_root_background_color_ = SK_ColorTRANSPARENT;
 
+  base::OneShotTimer mouse_wheel_end_dispatch_timer_;
+
   // Factory used to safely scope delayed calls to ShutdownHost().
   base::WeakPtrFactory<RenderWidgetHostViewMac> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewMac);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_MAC_H_