Fix x64 build.

src/x64/codegen-x64.h

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 506 matching lines @@
   void GenerateSetValueOf(ZoneList<Expression*>* args);
 
   // Fast support for charCodeAt(n).
   void GenerateFastCharCodeAt(ZoneList<Expression*>* args);
 
   // Fast support for object equality testing.
   void GenerateObjectEquals(ZoneList<Expression*>* args);
 
   void GenerateLog(ZoneList<Expression*>* args);
 
+  // Fast support for Math.random().
+  void GenerateRandomPositiveSmi(ZoneList<Expression*>* args);
 
   // Methods and constants for fast case switch statement support.
   //
   // Only allow fast-case switch if the range of labels is at most
   // this factor times the number of case labels.
   // Value is derived from comparing the size of code generated by the normal
   // switch code for Smi-labels to the size of a single pointer. If code
   // quality increases this number should be decreased to match.
   static const int kFastSwitchMaxOverheadFactor = 5;
 
@@ skipping 90 matching lines @@
   friend class Reference;
   friend class Result;
 
   DISALLOW_COPY_AND_ASSIGN(CodeGenerator);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_CODEGEN_X64_H_