Delete obviously unneeded forward declarations in chrome/browser/*.h.

chrome/browser/js_modal_dialog.h

 // Copyright (c) 2009 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_JS_MODAL_DIALOG_H_
 #define CHROME_BROWSER_JS_MODAL_DIALOG_H_
 #pragma once
 
 #include <string>
 
 #include "build/build_config.h"
 #include "chrome/browser/app_modal_dialog.h"
 #include "chrome/common/notification_observer.h"
 #include "chrome/common/notification_registrar.h"
 #include "net/base/cookie_monster.h"
 
 #if defined(OS_MACOSX)
 #if __OBJC__
 @class NSAlert;
 #else
 class NSAlert;
 #endif
 #endif
 
 class ExtensionHost;
 class JavaScriptMessageBoxClient;
 
+namespace IPC {
+class Message;
+}
+
 // A controller+model class for JavaScript alert, confirm, prompt, and
 // onbeforeunload dialog boxes.
 class JavaScriptAppModalDialog : public AppModalDialog,
                                  public NotificationObserver {
  public:
   // A union of data necessary to determine the type of message box to
   // show.  |dialog_flags| is a MessageBox flag.
   JavaScriptAppModalDialog(JavaScriptMessageBoxClient* client,
                            const std::wstring& title,
                            int dialog_flags,
@@ skipping 71 matching lines @@
   std::wstring message_text_;
   std::wstring default_prompt_text_;
   bool display_suppress_checkbox_;
   bool is_before_unload_dialog_;
   IPC::Message* reply_msg_;
 
   DISALLOW_COPY_AND_ASSIGN(JavaScriptAppModalDialog);
 };
 
 #endif  // CHROME_BROWSER_JS_MODAL_DIALOG_H_