Add snapshot option to test runner

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 1076 matching lines @@
   result.add_option("--build-only", help="Only build requirements, don't run the tests",
       default=False, action="store_true")
   result.add_option("--report", help="Print a summary of the tests to be run",
       default=False, action="store_true")
   result.add_option("-s", "--suite", help="A test suite",
       default=[], action="append")
   result.add_option("-t", "--timeout", help="Timeout in seconds",
       default=60, type="int")
   result.add_option("--arch", help='The architecture to run tests for',
       default='none')
+  result.add_option("--snapshot", help="Run the tests with snapshot turned on",
+      default=False, action="store_true")
   result.add_option("--simulator", help="Run tests with architecture simulator",
       default='none')
   result.add_option("--special-command", default=None)
   result.add_option("--valgrind", help="Run tests through valgrind",
       default=False, action="store_true")
   result.add_option("--cat", help="Print the source of the tests",
       default=False, action="store_true")
   result.add_option("--warn-unused", help="Report unused rules",
       default=False, action="store_true")
   result.add_option("-j", help="The number of parallel tasks to run",
@@ skipping 25 matching lines @@
         print "Architecture %s does not match sim %s" %(options.arch, options.simulator)
         return False
     # Ensure that the simulator argument is handed down to scons.
     options.scons_flags.append("simulator=" + options.simulator)
   else:
     # If options.arch is not set by the command line and no simulator setting
     # was found, set the arch to the guess.
     if options.arch == 'none':
       options.arch = ARCH_GUESS
     options.scons_flags.append("arch=" + options.arch)
+  if options.snapshot:
+    options.scons_flags.append("snapshot=on")
   return True
 
 
 REPORT_TEMPLATE = """\
 Total: %(total)i tests
  * %(skipped)4d tests will be skipped
  * %(nocrash)4d tests are expected to be flaky but not crash
  * %(pass)4d tests are expected to pass
  * %(fail_ok)4d tests are expected to fail that we won't fix
  * %(fail)4d tests are expected to fail that we should fix\
@@ skipping 194 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())