mac: History swiping doesn't work right with iframes.

content/browser/renderer_host/render_widget_host_view_mac.h

Index: content/browser/renderer_host/render_widget_host_view_mac.h
diff --git a/content/browser/renderer_host/render_widget_host_view_mac.h b/content/browser/renderer_host/render_widget_host_view_mac.h
index 6dd7d6660df08725b22b8465e9c18d929e68b091..31574fb8e4fe647a241b76d4f8887a735e9ceaac 100644
--- a/content/browser/renderer_host/render_widget_host_view_mac.h
+++ b/content/browser/renderer_host/render_widget_host_view_mac.h
@@ -330,8 +330,8 @@ class CONTENT_EXPORT RenderWidgetHostViewMac
       bool is_pinned_to_left, bool is_pinned_to_right) OVERRIDE;
   virtual bool LockMouse() OVERRIDE;
   virtual void UnlockMouse() OVERRIDE;
-  virtual void UnhandledWheelEvent(
-      const blink::WebMouseWheelEvent& event) OVERRIDE;
+  virtual void ProcessedWheelEvent(const blink::WebMouseWheelEvent& event,
+                                   bool consumed) OVERRIDE;
 
   // IPC::Sender implementation.
   virtual bool Send(IPC::Message* message) OVERRIDE;