chrome: Cleanup class/struct forward declarations

chrome/browser/ui/signin_view_controller.h

 // Copyright 2016 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_SIGNIN_VIEW_CONTROLLER_H_
 #define CHROME_BROWSER_UI_SIGNIN_VIEW_CONTROLLER_H_
 
 #include "base/macros.h"
 #include "chrome/browser/ui/profile_chooser_constants.h"
 
 class Browser;
 class SigninViewControllerDelegate;
-class Profile;
 
 namespace signin_metrics {
 enum class AccessPoint;
 }
 
 // Class responsible for showing and hiding the Signin and Sync Confirmation
 // tab-modal dialogs.
 class SigninViewController {
  public:
   SigninViewController();
@@ skipping 27 matching lines @@
     return signin_view_controller_delegate_;
   }
 
  private:
   SigninViewControllerDelegate* signin_view_controller_delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(SigninViewController);
 };
 
 #endif  // CHROME_BROWSER_UI_SIGNIN_VIEW_CONTROLLER_H_