[test] Fix test group expansion in test runner.

tools/run-tests.py

 #!/usr/bin/env python
 #
 # 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
@@ skipping 575 matching lines @@
   suite_paths = utils.GetSuitePaths(join(BASE_DIR, "test"))
 
   # Use default tests if no test configuration was provided at the cmd line.
   if len(args) == 0:
     args = ["default"]
 
   # Expand arguments with grouped tests. The args should reflect the list of
   # suites as otherwise filters would break.
   def ExpandTestGroups(name):
     if name in TEST_MAP:
-      return [suite for suite in TEST_MAP[arg]]
+      return [suite for suite in TEST_MAP[name]]
     else:
       return [name]
   args = reduce(lambda x, y: x + y,
          [ExpandTestGroups(arg) for arg in args],
          [])
 
   args_suites = OrderedDict() # Used as set
   for arg in args:
     args_suites[arg.split('/')[0]] = True
   suite_paths = [ s for s in args_suites if s in suite_paths ]
@@ skipping 200 matching lines @@
   if exit_code == 1 and options.json_test_results:
     print("Force exit code 0 after failures. Json test results file generated "
           "with failure information.")
     exit_code = 0
 
   return exit_code
 
 
 if __name__ == "__main__":
   sys.exit(Main())