[Mac] Factor out keyboard shortcut handling from ChromeEventProcessingWindow.

chrome/browser/ui/cocoa/chrome_command_dispatch_delegate.h

+// Copyright 2015 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_CHROME_COMMAND_DISPATCH_DELEGATE_H_
+#define CHROME_BROWSER_UI_COCOA_CHROME_COMMAND_DISPATCH_DELEGATE_H_
+
+#import <Cocoa/Cocoa.h>
+
+#import "ui/base/cocoa/command_dispatch_delegate.h"
+
+// Implement CommandDispatchDelegate by intercepting browser window keyboard
+// shortcuts and executing them with chrome::ExecuteCommand.
+@interface ChromeCommandDispatchDelegate : NSObject<CommandDispatchDelegate> {
+ @private
+  BOOL redispatchingEvent_;
+  BOOL eventHandled_;
+}
+
+// Checks if |event| is a window, delayed window, or browser keyboard shortcut.
+// (See global_keyboard_shortcuts_mac.h for details). If so, execute the
+// associated command. Returns YES if the event was handled.
+- (BOOL)handleExtraKeyboardShortcut:(NSEvent*)event window:(NSWindow*)window;
+
+@end
+
+#endif  // CHROME_BROWSER_UI_COCOA_CHROME_COMMAND_DISPATCH_DELEGATE_H_