Use auto-generated v8 version when building.

tools/gyp/v8.gyp

 # Copyright 2012 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 871 matching lines @@
         '../../src/utils.cc',
         '../../src/utils.h',
         '../../src/v8.cc',
         '../../src/v8.h',
         '../../src/v8memory.h',
         '../../src/v8threads.cc',
         '../../src/v8threads.h',
         '../../src/variables.cc',
         '../../src/variables.h',
         '../../src/vector.h',
-        '../../src/version.cc',
+        '../../src/version_gen.cc',
         '../../src/version.h',
         '../../src/vm-state-inl.h',
         '../../src/vm-state.h',
         '../../src/zone-inl.h',
         '../../src/zone.cc',
         '../../src/zone.h',
         '../../src/third_party/fdlibm/fdlibm.cc',
         '../../src/third_party/fdlibm/fdlibm.h',
       ],
       'conditions': [
@@ skipping 907 matching lines @@
         }],
         ['want_separate_host_toolset==1', {
           'toolsets': ['host'],
         }, {
           'toolsets': ['target'],
         }],
       ],
     },
   ],
 }