Add chromedriver_unittests to masters.

tests/data/trymail_tests/buildrunner_tryserver.in

 {
   'build_step_props': {
     'blamelist': [u'iannucci@chromium.org'],
     'branch': None,
     'buildername': 'win_rel',
     'buildnumber': 102110,
     'clobber': True,
     'got_nacl_revision': 10619,
     'got_revision': 178097,
     'got_v8_revision': 13451,
@@ skipping 44 matching lines @@
     step('manifest_to_hashes', result=results.SKIPPED),
     step('trigger_swarm_triggered', result=results.SKIPPED),
     step('start_crash_handler'),
     step('interactive_ui_tests'),
     step('check_deps2git', result=results.SKIPPED),
     step('check_deps2submodules', result=results.SKIPPED),
     step('check_deps', result=results.SKIPPED),
     step('base_unittests', result=results.SKIPPED),
     step('cacheinvalidation_unittests', result=results.SKIPPED),
     step('cc_unittests', result=results.SKIPPED),
+    step('chromedriver_unittests', result=results.SKIPPED),
     step('chromedriver2_unittests', result=results.SKIPPED),
     step('components_unittests', result=results.SKIPPED),
     step('courgette_unittests', result=results.SKIPPED),
     step('crypto_unittests', result=results.SKIPPED),
     step('url_unittests', result=results.SKIPPED),
     step('url_unittests_buildrunner_ignore', hidden=True),
     step('gpu_unittests', result=results.SKIPPED),
     step('jingle_unittests', result=results.SKIPPED),
     step('device_unittests', result=results.SKIPPED),
     step('media_unittests', result=results.SKIPPED),
@@ skipping 22 matching lines @@
     step('chrome_frame_unittests', result=results.SKIPPED),
     step('chrome_frame_tests', result=results.SKIPPED),
     step('nacl_integration', result=results.SKIPPED),
     step('process_dumps'),
   ],
   'master': {
     'getTitle()': 'Title',
     'getBuildbotURL()': 'http://build.chromium.org/p/tryserver.chromium/',
   },
 }