Switch nacl-clang back to gas in SCons

tests/trusted_crash/osx_crash_forwarding/nacl.scons

Index: tests/trusted_crash/osx_crash_forwarding/nacl.scons
diff --git a/tests/trusted_crash/osx_crash_forwarding/nacl.scons b/tests/trusted_crash/osx_crash_forwarding/nacl.scons
index 84e259b5b444698b5896217e9d29d8ecc69122fe..0b832a3b87086ab54278d29084d56bcc5cc13a88 100644
--- a/tests/trusted_crash/osx_crash_forwarding/nacl.scons
+++ b/tests/trusted_crash/osx_crash_forwarding/nacl.scons
@@ -15,12 +15,6 @@ if not env.Bit('host_mac'):
 if env.Bit('pnacl_generate_pexe'):
   Return()
 
-# This test uses the nexe built by exception_test, which currently doesn't
-# build with nacl_clang. See
-# https://code.google.com/p/nativeclient/issues/detail?id=3969
-if env.Bit('nacl_clang'):
-  Return()
-
 if 'TRUSTED_ENV' not in env:
   Return()
 trusted_env = env['TRUSTED_ENV']