Pass G_SLICE=always-malloc to swarmed ASan tasks.

testing/test_env.py

 #!/usr/bin/env python
 # Copyright (c) 2012 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.
 
 """Sets environment variables needed to run a chromium unit test."""
 
 import os
 import stat
 import subprocess
@@ skipping 63 matching lines @@
     out.insert(0, sys.executable)
   return out
 
 
 def get_asan_env(cmd, lsan):
   """Returns the envirnoment flags needed for ASan and LSan."""
 
   extra_env = {}
 
   # Instruct GTK to use malloc while running ASan or LSan tests.
-  # TODO(earthdok): enabling G_SLICE gives these leaks, locally and on swarming
-  #0 0x62c01b in __interceptor_malloc (/tmp/run_tha_testXukBDT/out/Release/browser_tests+0x62c01b)
-  #1 0x7fb64ab64a38 in g_malloc /build/buildd/glib2.0-2.32.4/./glib/gmem.c:159
-  #extra_env['G_SLICE'] = 'always-malloc'
+  extra_env['G_SLICE'] = 'always-malloc'
 
   extra_env['NSS_DISABLE_ARENA_FREE_LIST'] = '1'
   extra_env['NSS_DISABLE_UNLOAD'] = '1'
 
   # TODO(glider): remove the symbolizer path once
   # https://code.google.com/p/address-sanitizer/issues/detail?id=134 is fixed.
   symbolizer_path = os.path.abspath(os.path.join(ROOT_DIR, 'third_party',
       'llvm-build', 'Release+Asserts', 'bin', 'llvm-symbolizer'))
 
   asan_options = []
@@ skipping 87 matching lines @@
     print >> sys.stderr, 'Failed to start %s' % cmd
     raise
 
 
 def main():
   return run_executable(sys.argv[1:], os.environ.copy())
 
 
 if __name__ == '__main__':
   sys.exit(main())