Share precompiled header setup for blink between Windows and Mac.

third_party/WebKit/Source/core/layout/LayoutThemeMac.h

 /*
  * This file is part of the theme implementation for form controls in WebCore.
  *
  * Copyright (C) 2005 Apple Computer, Inc.
  * Copyright (C) 2008, 2009 Google, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */
 
 #ifndef LayoutThemeMac_h
 #define LayoutThemeMac_h
 
+#import <Cocoa/Cocoa.h>
+
 #import "core/layout/LayoutTheme.h"
 #import "core/paint/ThemePainterMac.h"
 #import "wtf/HashMap.h"
 #import "wtf/RetainPtr.h"
 
 OBJC_CLASS BlinkLayoutThemeNotificationObserver;
 
 namespace blink {
 
 class LayoutThemeMac final : public LayoutTheme {
@@ skipping 161 matching lines @@
   mutable HashMap<int, RGBA32> m_systemColorCache;
 
   RetainPtr<BlinkLayoutThemeNotificationObserver> m_notificationObserver;
 
   ThemePainterMac m_painter;
 };
 
 }  // namespace blink
 
 #endif  // LayoutThemeMac_h