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

public/platform/WebTraceLocation.h

Index: public/platform/WebTraceLocation.h
diff --git a/public/platform/WebTraceLocation.h b/public/platform/WebTraceLocation.h
index dfa73fbc7b091c94c48ca1f53776ae48ef6efadc..129c27720ed07fa51454c7da620148f4fd51aa75 100644
--- a/public/platform/WebTraceLocation.h
+++ b/public/platform/WebTraceLocation.h
@@ -7,6 +7,7 @@
 
 #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.
@@ -26,6 +27,7 @@ private:
 };
 
 #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