mac: Only let two-finger-scrolling trigger history if web doesn't swallow gesture

content/browser/renderer_host/render_widget_host_view.h

 // Copyright (c) 2011 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_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_H_
 #pragma once
 
 #if defined(OS_MACOSX)
 #include <OpenGL/OpenGL.h>
 #endif
 
 #include <string>
 #include <vector>
 
 #include "base/process_util.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkColor.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebInputEvent.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPopupType.h"
 #include "ui/base/ime/text_input_type.h"
 #include "ui/base/range/range.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/surface/transport_dib.h"
 
 namespace gfx {
 class Rect;
 class Size;
@@ skipping 260 matching lines @@
   virtual gfx::PluginWindowHandle GetCompositingSurface() = 0;
 
   // Toggles visual muting of the render view area. This is on when a
   // constrained window is showing, for example. |color| is the shade of
   // the overlay that covers the render view. If |animate| is true, the overlay
   // gradually fades in; otherwise it takes effect immediately. To remove the
   // fade effect, pass a NULL value for |color|. In this case, |animate| is
   // ignored.
   virtual void SetVisuallyDeemphasized(const SkColor* color, bool animate) = 0;
 
+  virtual void UnhandledWheelEvent(const WebKit::WebMouseWheelEvent& event) = 0;
+
+  virtual void SetHasHorizontalScrollbar(bool has_horizontal_scrollbar) = 0;
+  virtual void SetScrollOffsetPinning(
+      bool is_pinned_to_left, bool is_pinned_to_right) = 0;
+
   void set_popup_type(WebKit::WebPopupType popup_type) {
     popup_type_ = popup_type;
   }
   WebKit::WebPopupType popup_type() const { return popup_type_; }
 
   // Subclasses should override this method to do what is appropriate to set
   // the custom background for their platform.
   virtual void SetBackground(const SkBitmap& background);
   const SkBitmap& background() const { return background_; }
 
@@ skipping 22 matching lines @@
 
   // The current reserved area in view coordinates where contents should not be
   // rendered to draw the resize corner, sidebar mini tabs etc.
   gfx::Rect reserved_rect_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostView);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_H_