ChromeOS does not seem to play well with xfinitywifi based on many feedback reports. Seems to be two major issues: (a) incorrect password (b) stuck behind a portal.

This bug is filed for (b) based on this feedback report: https://feedback.corp.google.com/product/208/neutron?lView=rd&lReport=18355804509

Relevant Chromium log snippets: 

[788:788:1202/192429:ERROR:device_event_log_impl.cc(140)] [19:24:29.344] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192434:ERROR:device_event_log_impl.cc(140)] [19:24:34.824] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192448:ERROR:device_event_log_impl.cc(140)] [19:24:48.248] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:1287:1202/192453:ERROR:cpu_data_collector.cc(279)] CPU freq stats not available in sysfs.
[788:10940:1202/192508:WARNING:server_connection_manager.cc(272)] ServerConnectionManager forcing SYNC_AUTH_ERROR
[788:10940:1202/192508:WARNING:syncer_proto_util.cc(341)] Error posting from syncer: Response Code (bogus on error): -1 Content-Length (bogus on error): -1 Server Status: SYNC_AUTH_ERROR
[788:788:1202/192512:ERROR:device_event_log_impl.cc(140)] [19:25:12.258] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:1277:1202/192520:ERROR:connection_factory_impl.cc(367)] Failed to connect to MCS endpoint with error -137
[788:1271:1202/192523:ERROR:cpu_data_collector.cc(279)] CPU freq stats not available in sysfs.
[788:1271:1202/192527:ERROR:device_status_collector.cc(125)] Unable to get volume status for /special/drive-93f76bb70131c7c4b030094e8e9afe573efa7337
[788:788:1202/192535:ERROR:device_event_log_impl.cc(140)] [19:25:35.059] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192538:WARNING:CONSOLE(1)] "This file is deprecated. Please use `iron-flex-layout/iron-flex-layout-classes.html`, and one of the specific dom-modules instead", source: <URL: 5> (1)
[788:788:1202/192538:WARNING:CONSOLE(1)] "This file is deprecated. Please use `iron-flex-layout/iron-flex-layout-classes.html`, and one of the specific dom-modules instead", source: <URL: 6> (1)
[788:788:1202/192538:WARNING:CONSOLE(0)] "/deep/ combinator is deprecated. See <URL: 7> for more details.", source:  (0)
[788:1271:1202/192539:ERROR:version_loader.cc(67)] No LSB version key: CHROMEOS_ARC_VERSION
[788:788:1202/192539:ERROR:device_event_log_impl.cc(140)] [19:25:39.680] Network: ui_proxy_config_service.cc:91 No configured NetworkState for guid: 
[788:1277:1202/192539:VERBOSE2:ppapi_plugin_process_host.cc(484)] ppapi plugin process launched.
[788:788:1202/192539:WARNING:user_image_source.cc(39)] Failed to deserialize account_id.
[788:788:1202/192551:ERROR:device_event_log_impl.cc(140)] [19:25:51.605] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:1271:1202/192553:ERROR:cpu_data_collector.cc(279)] CPU freq stats not available in sysfs.
[788:788:1202/192555:ERROR:device_event_log_impl.cc(140)] [19:25:55.120] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192558:ERROR:device_event_log_impl.cc(140)] [19:25:58.707] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192606:ERROR:device_event_log_impl.cc(140)] [19:26:06.676] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192607:ERROR:CONSOLE(127)] "Uncaught TypeError: Cannot read property 'time' of undefined", source: <URL: 8> (127)
[788:788:1202/192610:ERROR:device_event_log_impl.cc(140)] [19:26:10.202] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:10940:1202/192616:WARNING:server_connection_manager.cc(272)] ServerConnectionManager forcing SYNC_AUTH_ERROR
[788:10940:1202/192616:WARNING:syncer_proto_util.cc(341)] Error posting from syncer: Response Code (bogus on error): -1 Content-Length (bogus on error): -1 Server Status: SYNC_AUTH_ERROR
[788:788:1202/192619:ERROR:device_event_log_impl.cc(140)] [19:26:19.273] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:1286:1202/192623:ERROR:cpu_data_collector.cc(279)] CPU freq stats not available in sysfs.
[788:788:1202/192625:ERROR:device_event_log_impl.cc(140)] [19:26:25.426] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192632:ERROR:device_event_log_impl.cc(140)] [19:26:32.551] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192643:ERROR:device_event_log_impl.cc(140)] [19:26:43.764] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192646:ERROR:CONSOLE(127)] "Uncaught TypeError: Cannot read property 'time' of undefined", source: <URL: 8> (127)
[788:788:1202/192647:ERROR:device_event_log_impl.cc(140)] [19:26:47.347] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192650:ERROR:device_event_log_impl.cc(140)] [19:26:50.916] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:1287:1202/192653:ERROR:cpu_data_collector.cc(279)] CPU freq stats not available in sysfs.
[788:788:1202/192658:ERROR:device_event_log_impl.cc(140)] [19:26:58.825] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:1277:1202/192659:ERROR:connection_factory_impl.cc(367)] Failed to connect to MCS endpoint with error -137
[788:788:1202/192702:ERROR:device_event_log_impl.cc(140)] [19:27:02.379] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192708:WARNING:device_management_service.cc(580)] Dmserver request failed, retrying in 20s.
[788:788:1202/192708:WARNING:device_management_service.cc(580)] Dmserver request failed, retrying in 0s.
[788:788:1202/192708:WARNING:device_management_service.cc(580)] Dmserver request failed, retrying in 0s.
[788:788:1202/192708:WARNING:device_management_service.cc(580)] Dmserver request failed, retrying in 0s.
[788:788:1202/192708:WARNING:device_management_service.cc(580)] Dmserver request failed, retrying in 0s.
[788:788:1202/192708:WARNING:device_management_service.cc(580)] Dmserver request failed, retrying in 0s.
[788:788:1202/192714:ERROR:device_event_log_impl.cc(140)] [19:27:14.583] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192721:ERROR:device_event_log_impl.cc(140)] [19:27:21.536] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:1286:1202/192723:ERROR:cpu_data_collector.cc(279)] CPU freq stats not available in sysfs.
[788:1287:1202/192727:ERROR:device_status_collector.cc(125)] Unable to get volume status for /special/drive-93f76bb70131c7c4b030094e8e9afe573efa7337
[788:788:1202/192729:ERROR:device_event_log_impl.cc(140)] [19:27:29.992] Network: network_portal_detector_impl.cc:463 Portal detection timeout:  name=xfinitywifi id=297441ff-14df-4fa9-8fcc-c53c22ae778a
[788:788:1202/192731:ERROR:device_event_log_impl.cc(140)] [19:27:31.971] Network: network_state_handler.cc:922 Default network in unexpected state: xfinitywifi (/service/3)State: idle
[788:788:1202/192731:WARNING:device_management_service.cc(580)] Dmserver request failed, retrying in 10s.
[788:788:1202/192731:WARNING:device_management_service.cc(580)] Dmserver request failed, retrying in 0s.
[788:788:1202/192731:WARNING:device_management_service.cc(580)] Dmserver request failed, retrying in 40s.