Remove obviously unneeded forward declarations in chrome/browser/[abef]*/*.h.

chrome/browser/extensions/extension_disabled_infobar_delegate.cc

 // Copyright (c) 2010 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.
 
 #include "chrome/browser/extensions/extension_disabled_infobar_delegate.h"
 
+#include <string>
+
 #include "app/l10n_util.h"
 #include "chrome/browser/chrome_thread.h"
 #include "chrome/browser/extensions/extension_install_ui.h"
 #include "chrome/browser/extensions/extensions_service.h"
 #include "chrome/browser/tab_contents/infobar_delegate.h"
 #include "chrome/browser/tab_contents/tab_contents.h"
 #include "chrome/browser/browser_list.h"
 #include "chrome/common/extensions/extension_file_util.h"
 #include "chrome/common/extensions/extension_resource.h"
 #include "chrome/common/notification_registrar.h"
@@ skipping 118 matching lines @@
 
   tab_contents->AddInfoBar(new ExtensionDisabledInfobarDelegate(
       tab_contents, service, extension));
 }
 
 void ShowExtensionDisabledDialog(ExtensionsService* service, Profile* profile,
                                  Extension* extension) {
   // This object manages its own lifetime.
   new ExtensionDisabledDialogDelegate(profile, service, extension);
 }