Enabled PyAuto on the Mac 10.6 bots.

SConstruct

Index: SConstruct
diff --git a/SConstruct b/SConstruct
index d318edc9df15022ccb3d7cef976c392c4bd1030f..317c12074535d11848fbc3a37a2506bcc7d5ddba 100755
--- a/SConstruct
+++ b/SConstruct
@@ -1291,9 +1291,15 @@ pre_base_env.AddMethod(PyAutoTester)
 # 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)