Change default build and test architecture to x64.

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 datetime
 import json
@@ skipping 40 matching lines @@
 def GuessArchitecture():
   os_id = platform.machine()
   if os_id.startswith('armv5te'):
     return 'armv5te'
   elif os_id.startswith('arm'):
     return 'arm'
   elif os_id.startswith('aarch64'):
     return 'arm64'
   elif os_id.startswith('mips'):
     return 'mips'
+  elif '64' in os_id:
+    return 'x64'
   elif (not os_id) or (not re.match('(x|i[3-6])86', os_id) is None):
     return 'ia32'
   elif os_id == 'i86pc':
     return 'ia32'
-  elif '64' in os_id:
-    return 'x64'
   else:
     guess_os = GuessOS()
     print "Warning: Guessing architecture %s based on os %s\n"\
           % (os_id, guess_os)
     if guess_os == 'win32':
       return 'ia32'
     return None
 
 
 # Try to guess the number of cpus on this machine.
@@ skipping 586 matching lines @@
     os.chdir(self._working_directory)
 
   def __exit__(self, *_):
     print "Enter directory = ", self._old_cwd
     os.chdir(self._old_cwd)
 
 
 if __name__ == "__main__":
   import sys
   Main()