Fix definition of V8_LIBRT_NOT_AVAILABLE in v8.gyp since we test for it using #elif in time.cc.

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 724 matching lines @@
                 #     }]
                 #   ]
                 # },
                 #
                 # but we can't do this right now, as the AOSP does not support
                 # linking against the host librt, so we need to work around this
                 # for now, using the following hack (see platform/time.cc):
                 'target_conditions': [
                   ['_toolset=="host"', {
                     'defines': [
-                      'V8_LIBRT_NOT_AVAILABLE',
+                      'V8_LIBRT_NOT_AVAILABLE=1',
                     ],
                   }],
                 ],
                 'sources': [
                   '../../src/platform-linux.cc'
                 ]
               }],
             ],
           },
         ],
@@ skipping 307 matching lines @@
         }],
         ['v8_compress_startup_data=="bz2"', {
           'libraries': [
             '-lbz2',
           ]
         }],
       ],
     },
   ],
 }