This change makes the help text for `--timeout` misleading:

> 'if a --timeout value is given, it will set the default page load timeout, search timeout and script timeout to the given value. If not passed in, it will use the default values of 30000ms for page load, 0ms for search timeout and 10000ms for script timeout'

http://hg.mozilla.org/mozilla-central/file/04bdb7369ba4/testing/marionette/client/marionette/runner/base.py#l470

We should see if we can address this in this patch.