MacViews: Handle three-finger swipe gestures for navigation.

chrome/browser/ui/views/frame/browser_view.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 CHROME_BROWSER_UI_VIEWS_FRAME_BROWSER_VIEW_H_
 #define CHROME_BROWSER_UI_VIEWS_FRAME_BROWSER_VIEW_H_
 
 #include <map>
 #include <memory>
 #include <string>
@@ skipping 417 matching lines @@
   gfx::Size GetMinimumSize() const override;
 
   // InfoBarContainerDelegate:
   SkColor GetInfoBarSeparatorColor() const override;
   void InfoBarContainerStateChanged(bool is_animating) override;
   bool DrawInfoBarArrows(int* x) const override;
 
   // Overridden from views::View:
   const char* GetClassName() const override;
   void Layout() override;
+  void OnGestureEvent(ui::GestureEvent* event) override;
   void ViewHierarchyChanged(
       const ViewHierarchyChangedDetails& details) override;
   void ChildPreferredSizeChanged(View* child) override;
   void GetAccessibleNodeData(ui::AXNodeData* node_data) override;
   void OnThemeChanged() override;
   void OnNativeThemeChanged(const ui::NativeTheme* theme) override;
 
   // Overridden from ui::AcceleratorTarget:
   bool AcceleratorPressed(const ui::Accelerator& accelerator) override;
 
@@ skipping 262 matching lines @@
   // The class that registers for keyboard shortcuts for extension commands.
   std::unique_ptr<ExtensionKeybindingRegistryViews>
       extension_keybinding_registry_;
 
   mutable base::WeakPtrFactory<BrowserView> activate_modal_dialog_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserView);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_FRAME_BROWSER_VIEW_H_