[Mac] Confirm-to-Quit: Wait for a KeyUp event if the user held Cmd+Q on the second tap.

chrome/browser/ui/cocoa/confirm_quit_panel_controller.h

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_UI_COCOA_CONFIRM_QUIT_PANEL_CONTROLLER_H_
 #define CHROME_BROWSER_UI_COCOA_CONFIRM_QUIT_PANEL_CONTROLLER_H_
 
 #import <Cocoa/Cocoa.h>
 
 #import "base/mac/cocoa_protocols.h"
 #include "ui/base/models/accelerator_cocoa.h"
 
 @class ConfirmQuitFrameView;
 
 // The ConfirmQuitPanelController manages the black HUD window that tells users
 // to "Hold Cmd+Q to Quit".
 @interface ConfirmQuitPanelController : NSWindowController<NSWindowDelegate> {
  @private
   // The content view of the window that this controller manages.
   ConfirmQuitFrameView* contentView_;  // Weak, owned by the window.
 }
 
 // Returns a singleton instance of the Controller. This will create one if it
 // does not currently exist.
 + (ConfirmQuitPanelController*)sharedController;
 
+// Checks whether the |event| should trigger the feature.
++ (BOOL)eventTriggersFeature:(NSEvent*)event;
+
+// Runs a modal loop that brings up the panel and handles the logic for if and
+// when to terminate. Returns NSApplicationTerminateReply for use in
+// -[NSApplicationDelegate applicationShouldTerminate:].
+- (NSApplicationTerminateReply)runModalLoopForApplication:(NSApplication*)app;
+
 // Shows the window.
 - (void)showWindow:(id)sender;
 
 // If the user did not confirm quit, send this message to give the user
 // instructions on how to quit.
 - (void)dismissPanel;
 
 // Returns the Accelerator for the Quit menu item.
 + (ui::AcceleratorCocoa)quitAccelerator;
 
 @end
 
 @interface ConfirmQuitPanelController (UnitTesting)
 - (NSString*)keyCombinationForAccelerator:(const ui::AcceleratorCocoa&)item;
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_CONFIRM_QUIT_PANEL_CONTROLLER_H_