Precompile Document.h and LayoutObject.h for Source/web

public/platform/WebTraceLocation.h

 // 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.
 
 #ifndef WebTraceLocation_h
 #define WebTraceLocation_h
 
 #include "WebCommon.h"
 
+#include "base/location.h"
 namespace blink {
 
 // This class is used to keep track of where posted tasks originate. See base/location.h in Chromium.
 // Currently only store the bits used in Blink, base::Location stores more.
 class BLINK_PLATFORM_EXPORT WebTraceLocation {
 public:
     // These char*s are not copied and must live for the duration of the program.
     WebTraceLocation(const char* function, const char* file);
     WebTraceLocation();
 
     const char* functionName() const;
     const char* fileName() const;
 
 private:
     const char* m_functionName;
     const char* m_fileName;
 };
 
 #if INSIDE_BLINK
+#undef FROM_HERE // The one from base/location.h we do not want right now.
 #define FROM_HERE ::blink::WebTraceLocation(__FUNCTION__, __FILE__)
 #endif // INSIDE_BLINK
 
 }
 
 #endif // WebTraceLocation_h