NaCl Proxy Test: enable ppapi_ppb_fullscreen_browser_test except for Mac.

ppapi/native_client/tests/ppapi_test_lib/nacl.scons

 # -*- python -*-
 # Copyright (c) 2011 The Chromium Authors.  All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 #
 # Test library for testing PPAPI C layer for PPB_ and PPP_ interfaces.
 #
 # TODO(polina): also factor in the C++ layer?
 # TODO(polina): add trusted build.scons.
 #
 # module_instance.cc - implements PPP and PPP_Instance interfaces.
 # get_browser_interface.cc - implements interface lookup helpers.
 # internal_utils.cc - implements internal helper functions and globals.
 # test_interface.cc - implements the test interface.
 #
 # See ppapi_test_example for sample usage.
 
 Import('env')
 
 # Register new tests here as we can no longer add them to the DEPS-ed in
 # native_client/SConstruct in the same CL.
 #
 # TODO(polina, bradnelson): take out this temporary work-around for adding new
 # tests when we have a common place to add these
 # (e.g. ppapi/native_client/nacl.scons) included into native_client/SConstruct.
 env_clone = env.Clone()
-# The test is flaky. Disable for now.
-#env_clone.SConscript('../ppapi_browser/ppb_fullscreen/nacl.scons',
-#                     exports=['env'])
+env_clone.SConscript('../ppapi_browser/ppb_fullscreen/nacl.scons',
+                     exports=['env'])
 
 env.Prepend(CPPDEFINES=['XP_UNIX'])
 
 env.ComponentLibrary('ppapi_test_lib',
                      ['get_browser_interface.cc',
                       'internal_utils.cc',
                       'testable_callback.cc',
                       'module_instance.cc',
                       'test_interface.cc'])