Remove some more OS_CHROMEOS from browser.

ash/shell_delegate.h

Index: ash/shell_delegate.h
===================================================================
--- ash/shell_delegate.h	(revision 137127)
+++ ash/shell_delegate.h	(working copy)
@@ -21,6 +21,10 @@
 class Window;
 }
 
+namespace ui {
+class AcceleratorTarget;
+}
+
 namespace views {
 class Widget;
 }
@@ -74,6 +78,9 @@
   // Invoked when the user needs to set up mobile networking.
   virtual void OpenMobileSetup() = 0;
 
+  // Shows the keyboard shortcut overlay.
+  virtual void ShowKeyboardOverlay(ui::AcceleratorTarget* target) = 0;
+
   // Get the current browser context. This will get us the current profile.
   virtual content::BrowserContext* GetCurrentBrowserContext() = 0;