Enabled PyAuto on the Mac 10.6 bots.

SConstruct

 # -*- python -*-
 # Copyright (c) 2011 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import atexit
 import glob
 import os
 import platform
 import stat
@@ skipping 1273 matching lines @@
                          osenv=osenv,
                          extra_deps=extra_deps)
 
 pre_base_env.AddMethod(PyAutoTester)
 
 
 # Disabled for ARM (because Chrome binaries for ARM are not available), on the
 # Chrome bots (because PyAuto is not expected to be available on them) and when
 # 32-bit test binaries are run on a 64-bit machine (because 32-bit python is not
 # available on 64-bit machines).
+# However, our Mac bots will have 32-bit versions of Python 2.5, even if they

[Mark Seaborn, 2011/07/27 00:44:27]

Please spell out the cases:
 * Mac OS X 10.5 bots have 32-bit Python 2.5 installed as part of the OS.
 * Mac OS X 10.6 bots have had 32-bit Python 2.5 manually installed.

+# are 64-bit machines.
+# TODO(ncbray): check the architechture of the Python that we plan to run,

[Mark Seaborn, 2011/07/27 00:44:27]

sp: architecture

+# rather than the architechture of Python currently running.

[Mark Seaborn, 2011/07/27 00:44:27]

ditto

 def PyAutoTesterIsBroken(env):
-  return (PPAPIBrowserTesterIsBroken(env) or
-          (env.Bit('build_x86_32') and platform.architecture()[0] == '64bit'))
+  return (PPAPIBrowserTesterIsBroken(env)
+          or (not env.Bit('host_mac')
+              and env.Bit('build_x86_32')
+              and platform.architecture()[0] == '64bit'))
 
 pre_base_env.AddMethod(PyAutoTesterIsBroken)
 
 
 # Disable async surfaway pyauto test suite on newlib until issues it raises on
 # bots are fixed.  TODO(nfullagar): re-enable when this suite for newlib when it
 # won't break the bots.
 def PyAutoTesterSurfawayAsyncIsBroken(env):
   return not env.Bit('nacl_glibc')
 
@@ skipping 1852 matching lines @@
   nacl_env.ValidateSdk()
 
 if BROKEN_TEST_COUNT > 0:
   msg = "There are %d broken tests." % BROKEN_TEST_COUNT
   if GetOption('brief_comstr'):
     msg += " Add --verbose to the command line for more information."
   print msg
 
 # separate warnings from actual build output
 Banner('B U I L D - O U T P U T:')