Implement a Menu Item to Hide the Toolbar in Fullscreen

chrome/browser/ui/browser_window.h

Index: chrome/browser/ui/browser_window.h
diff --git a/chrome/browser/ui/browser_window.h b/chrome/browser/ui/browser_window.h
index b377723a4d64556da41929752ca1cd52cc59ab60..297e065c121b07cc55470777f919219a0c97b6bc 100644
--- a/chrome/browser/ui/browser_window.h
+++ b/chrome/browser/ui/browser_window.h
@@ -148,9 +148,10 @@ class BrowserWindow : public ui::BaseWindow {
   // Show or hide the tab strip, toolbar and bookmark bar when in browser
   // fullscreen.
   // Currently only supported on Mac.
-  virtual bool SupportsFullscreenWithToolbar() const = 0;
   virtual void UpdateFullscreenWithToolbar(bool with_toolbar) = 0;
+  virtual void ToggleFullscreenToolbar() = 0;
   virtual bool IsFullscreenWithToolbar() const = 0;
+  virtual bool ShouldHideFullscreenToolbar() const = 0;
 
 #if defined(OS_WIN)
   // Sets state for entering or exiting Win8 Metro snap mode.