Reenable ctrl-c on tools/test by removing intialization of result in Run.

tools/test.py

 #!/usr/bin/env python
 #
 # Copyright 2008 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
@@ skipping 361 matching lines @@
     pass
 
   def AfterRun(self, result):
     pass
 
   def GetCustomFlags(self, mode):
     return None
 
   def Run(self):
     self.BeforeRun()
-    result = "exception"
     try:
       result = self.RunCommand(self.GetCommand())
     finally:
       self.AfterRun(result)
     return result
 
   def Cleanup(self):
     return
 
 
@@ skipping 1088 matching lines @@
     for entry in timed_tests[:20]:
       t = FormatTime(entry.duration)
       sys.stderr.write("%4i (%s) %s\n" % (index, t, entry.GetLabel()))
       index += 1
 
   return result
 
 
 if __name__ == '__main__':
   sys.exit(Main())