Fixes monkey test timeout

Monkey test has its own timeout which varies by the number of events, so pass None for the test_dispatcher timeout.

NOTRY=True
BUG=

Review URL: https://chromiumcodereview.appspot.com/22939002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@217072 0039d316-1c4b-4281-b951-d872f2087c98

build/android/test_runner.py

@@ -542,7 +542,7 @@ def _RunMonkeyTests(options, error_func):
   runner_factory, tests = monkey_setup.Setup(monkey_options)
 
   results, exit_code = test_dispatcher.RunTests(
-      tests, runner_factory, False, None, shard=False)
+      tests, runner_factory, False, None, shard=False, test_timeout=None)
 
   report_results.LogFull(
       results=results,