mac: Fix bug where exiting tab fullscreen would cause Chrome menubar to disappear.

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 2c8b89c6f749bfef3bb1cd7c1ddc04dcda83a918..ce18e71e92dadfd01522daf11f24abc9b1e54862 100644
--- a/chrome/browser/ui/browser_window.h
+++ b/chrome/browser/ui/browser_window.h
@@ -313,12 +313,13 @@ class BrowserWindow : public ui::BaseWindow {
   virtual void Paste() = 0;
 
 #if defined(OS_MACOSX)
-  // Enters Mac specific fullscreen mode with chrome displayed (e.g. omnibox)
-  // on OSX 10.7+, a.k.a. Lion Fullscreen mode.
-  // Invalid to call on OSX earlier than 10.7.
-  // Enters either from non fullscreen, or from fullscreen without chrome.
-  // Exit to normal fullscreen with EnterFullscreen().
+  // The following two methods cause the browser window to enter AppKit
+  // Fullscreen. The methods are idempotent. The methods are invalid to call on
+  // OSX 10.6. One method displays chrome (e.g. omnibox, tabstrip), whereas the
+  // other method hides it.
   virtual void EnterFullscreenWithChrome() = 0;
+  virtual void EnterFullscreenWithoutChrome() = 0;
+
   virtual bool IsFullscreenWithChrome() = 0;
   virtual bool IsFullscreenWithoutChrome() = 0;
 #endif