Kibana doesn't let you save field editor changes if user has discover open in another tab and making config changes (adding fields as columns)

[bhavyarm]

Kibana version: 6.4.0 BC3

Browser version: chrome latest

Browser OS version: os x

Original install method (e.g. download page, yum, from source, etc.): from staging

Describe the bug: If user has discover open in a different tab and field editor open in a different tab - and changes the config by adding columns in discover and tries to save the changes in the field editor at the same time - Kibana doesn't let the user save. There are no messages too.

Steps to reproduce:

1. Open Kibana in two tabs - one has field editor and one has discover
2. Add a field in discover as column
3. Make changes to a field in field editor and try to save it
4. The changes won't get saved and there are no messages from Kibana.

Errors in browser console (if relevant):

commons.bundle.js:3 PUT https://localhost:5601/api/saved_objects/index-pattern/e0641650-9be2-11e8-aca2-b984e3e8f789 409 (Conflict)
(anonymous) @ commons.bundle.js:3
tryCatch @ vendors.bundle.js:8
(anonymous) @ vendors.bundle.js:8
prototype.(anonymous function) @ vendors.bundle.js:8
step @ commons.bundle.js:3
(anonymous) @ commons.bundle.js:3
(anonymous) @ commons.bundle.js:3
(anonymous) @ commons.bundle.js:3
kfetch @ commons.bundle.js:3
value @ commons.bundle.js:3
SavedObjectsClient.update @ commons.bundle.js:3
update @ commons.bundle.js:3
value @ commons.bundle.js:3
value @ commons.bundle.js:3
$scope.removeColumn @ kibana.bundle.js:18
$scope.toggleDisplay @ kibana.bundle.js:18
fn @ VM4438:4
callback @ vendors.bundle.js:133
$eval @ vendors.bundle.js:133
$apply @ vendors.bundle.js:133
(anonymous) @ vendors.bundle.js:133
dispatch @ vendors.bundle.js:128
elemData.handle @ vendors.bundle.js:128
vendors.bundle.js:133 Error: Conflict
    at commons.bundle.js:3
    at tryCatch (vendors.bundle.js:8)
    at Generator._invoke (vendors.bundle.js:8)
    at Generator.prototype.(anonymous function) [as next] (https://localhost:5601/bundles/vendors.bundle.js:8:904906)
    at step (commons.bundle.js:3)
    at commons.bundle.js:3 "Possibly unhandled rejection: {"res":{},"body":{"message":"[doc][index-pattern:e0641650-9be2-11e8-aca2-b984e3e8f789]: version conflict, current version [16] is different than the one provided [14]: [version_conflict_engine_exception] [doc][index-pattern:e0641650-9be2-11e8-aca2-b984e3e8f789]: version conflict, current version [16] is different than the one provided [14], with { index_uuid=\"cf8-bwOjS3ey20ghRHBDNg\" & shard=\"0\" & index=\".kibana\" }","statusCode":409,"error":"Conflict"}}"
(anonymous) @ vendors.bundle.js:133
(anonymous) @ vendors.bundle.js:133
processChecks @ vendors.bundle.js:133
$digest @ vendors.bundle.js:133
(anonymous) @ vendors.bundle.js:133
completeOutstandingRequest @ vendors.bundle.js:133
(anonymous) @ vendors.bundle.js:133
setTimeout (async)
Browser.self.defer @ vendors.bundle.js:133
$evalAsync @ vendors.bundle.js:133
closePopover @ commons.bundle.js:3
EuiOutsideClickDetector._this.onClickOutside @ vendors.bundle.js:149

[bhavyarm]

cc @jen-huang looks like connected to changes in #20245

[jen-huang]

This is probably due to the new UI not surfacing version conflict errors. Investigating.