[Mac] Show correct cursor after context menu is closed.

chrome/browser/renderer_host/render_widget_host_view_mac.h

Index: chrome/browser/renderer_host/render_widget_host_view_mac.h
===================================================================
--- chrome/browser/renderer_host/render_widget_host_view_mac.h	(revision 91505)
+++ chrome/browser/renderer_host/render_widget_host_view_mac.h	(working copy)
@@ -207,6 +207,7 @@
   virtual void SetTooltipText(const std::wstring& tooltip_text) OVERRIDE;
   virtual void SelectionChanged(const std::string& text,
                                 const ui::Range& range) OVERRIDE;
+  virtual void ShowingContextMenu(bool showing) OVERRIDE;
   virtual BackingStore* AllocBackingStore(const gfx::Size& size) OVERRIDE;
   virtual void SetTakesFocusOnlyOnMouseDown(bool flag) OVERRIDE;
   // See comment in RenderWidgetHostView!
@@ -369,6 +370,9 @@
   // true if the View is not visible.
   bool is_hidden_;
 
+  // Whether we are showing a context menu.
+  bool is_showing_context_menu_;
+
   // The text to be shown in the tooltip, supplied by the renderer.
   std::wstring tooltip_text_;