Allow multiple devices on bisects hosts

scripts/slave/recipe_modules/chromium_android/example.expected/webview_cts_unexecuted_tests.json

 [
   {
     "cmd": [
       "python",
       "-u",
       "\nimport os, sys\n\nbuild_path = sys.argv[1]\nif os.path.exists(build_path):\n  for (path, dir, files) in os.walk(build_path):\n    for cur_file in files:\n      if cur_file.endswith('index.lock'):\n        path_to_file = os.path.join(path, cur_file)\n        print 'deleting %s' % path_to_file\n        os.remove(path_to_file)\n",
       "[SLAVE_BUILD]"
     ],
     "name": "cleanup index.lock",
     "~followup_annotations": [
@@ skipping 744 matching lines @@
     "name": "Run CTS",
     "stdout": "/path/to/tmp/",
     "~followup_annotations": [
       "@@@STEP_LOG_LINE@stdout@Created xml report file at file:///path/to/testResult.xml@@@",
       "@@@STEP_LOG_END@stdout@@@",
       "@@@STEP_LOG_LINE@disabled_tests@@@@",
       "@@@STEP_LOG_LINE@disabled_tests@                        {@@@",
       "@@@STEP_LOG_LINE@disabled_tests@                          \"android.webkit.cts.ExampleBlacklistedTest\":@@@",
       "@@@STEP_LOG_LINE@disabled_tests@                            [@@@",
       "@@@STEP_LOG_LINE@disabled_tests@                              {@@@",
-      "@@@STEP_LOG_LINE@disabled_tests@                                \"name\": \"testA\",@@@",
+      "@@@STEP_LOG_LINE@disabled_tests@                                \"name\": \"testA\", @@@",
       "@@@STEP_LOG_LINE@disabled_tests@                                \"_bug_id\": \"crbug.com/123\"@@@",
       "@@@STEP_LOG_LINE@disabled_tests@                              },@@@",
       "@@@STEP_LOG_LINE@disabled_tests@                              {\"name\": \"testB\"}@@@",
       "@@@STEP_LOG_LINE@disabled_tests@                            ]@@@",
       "@@@STEP_LOG_LINE@disabled_tests@                          }@@@",
       "@@@STEP_LOG_END@disabled_tests@@@"
     ]
   },
   {
     "cmd": [
       "python",
       "-u",
       "\nimport shutil\nimport sys\nshutil.copy(sys.argv[1], sys.argv[2])\n",
       "/path/to/testResult.xml",
       "/path/to/tmp/"
     ],
     "name": "Read test result and report failures",
     "~followup_annotations": [
       "@@@STEP_TEXT@<br/>not executed:<br/>android.webkit.cts.WebSettingsTest#test<br/>@@@",
       "@@@STEP_FAILURE@@@"
     ]
   },
   {
     "name": "$result",
     "reason": "Tests not executed.",
     "status_code": 1
   }
 ]