Added support for using a checked-in binary of dart for ARM

tools/utils.py

 # Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 # This file contains a set of utilities functions used by other Python-based
 # scripts.
 
 import commands
 import os
 import platform
@@ skipping 419 matching lines @@
   with file(name, 'a'):
     os.utime(name, None)
 
 
 def DartBinary():
   tools_dir = os.path.dirname(os.path.realpath(__file__))
   dart_binary_prefix = os.path.join(tools_dir, 'testing', 'bin')
   if IsWindows():
     return os.path.join(dart_binary_prefix, 'windows', 'dart.exe')
   else:
-    return os.path.join(dart_binary_prefix, GuessOS(), 'dart')
+    arch = GuessArchitecture()
+    system = GuessOS()
+    if arch == 'arm':
+      return os.path.join(dart_binary_prefix, system, 'dart-arm')
+    else:
+      return os.path.join(dart_binary_prefix, system, 'dart')
 
 
 def DartSdkBinary():
   tools_dir = os.path.dirname(os.path.realpath(__file__))
   dart_binary_prefix = os.path.join(tools_dir, '..', 'sdk' , 'bin')
   return os.path.join(dart_binary_prefix, 'dart')
 
 class TempDir(object):
   def __init__(self, prefix=''):
     self._temp_dir = None
     self._prefix = prefix
 
   def __enter__(self):
     self._temp_dir = tempfile.mkdtemp(self._prefix)
     return self._temp_dir
 
   def __exit__(self, *_):
     shutil.rmtree(self._temp_dir, ignore_errors=True)
 
 
 if __name__ == "__main__":
   import sys
   Main(sys.argv)