MacViews: Fix a forward declare of InputMethodDelegate in native_widget_private.h

ui/views/widget/native_widget_mac.mm

 // Copyright 2014 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 "ui/views/widget/native_widget_mac.h"
 
 #include <Cocoa/Cocoa.h>
 
 #include "ui/gfx/font_list.h"
 
@@ skipping 111 matching lines @@
 bool NativeWidgetMac::HasCapture() const {
   NOTIMPLEMENTED();
   return false;
 }
 
 InputMethod* NativeWidgetMac::CreateInputMethod() {
   NOTIMPLEMENTED();
   return NULL;
 }
 
-InputMethodDelegate* NativeWidgetMac::GetInputMethodDelegate() {
+internal::InputMethodDelegate* NativeWidgetMac::GetInputMethodDelegate() {
   NOTIMPLEMENTED();
   return NULL;
 }
 
 ui::InputMethod* NativeWidgetMac::GetHostInputMethod() {
   NOTIMPLEMENTED();
   return NULL;
 }
 
 void NativeWidgetMac::CenterWindow(const gfx::Size& size) {
@@ skipping 289 matching lines @@
 }
 
 // static
 gfx::FontList NativeWidgetPrivate::GetWindowTitleFontList() {
   NOTIMPLEMENTED();
   return gfx::FontList();
 }
 
 }  // namespace internal
 }  // namespace views