Make escape exit tabbed fullscreen mode even if browser was in fullscreen mode before.

chrome/browser/ui/browser.cc

Index: chrome/browser/ui/browser.cc
diff --git a/chrome/browser/ui/browser.cc b/chrome/browser/ui/browser.cc
index e1b9c58f35c53810d28882f502a2d578e9c4d3d9..94070b0b78bbfbec05489c4f0d614f61b8f0386c 100644
--- a/chrome/browser/ui/browser.cc
+++ b/chrome/browser/ui/browser.cc
@@ -3700,6 +3700,12 @@ void Browser::ViewSourceForFrame(TabContents* source,
 
 bool Browser::PreHandleKeyboardEvent(const NativeWebKeyboardEvent& event,
                                      bool* is_keyboard_shortcut) {
+  // Escape exits tabbed fullscreen mode.
+  // TODO(koz): Write a test for this http://crbug.com/100441.
+  if (event.windowsKeyCode == 27 && fullscreened_tab_) {
+    ExitTabbedFullscreenModeIfNecessary();
+    return true;
+  }
   return window()->PreHandleKeyboardEvent(event, is_keyboard_shortcut);
 }