previewConversationAfterFindExisting more flow types (#16795)
previewConversationAfterFindExisting more flow types (#16795)

* use callPromise

* use half result

keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client