would only work in the case where onSaveInstanceState was called.
- combined mExistingAccounts and mSavedAccounts into one field
- set this field when starting the addAccount request
- write this to the instance state if the request state
is ADDING_ACCOUNT
- read this field from the instance state, if any,
when the request state is ADDING_ACCOUNT
Bug: 5459669
Change-Id: I5a7b4943de8e706cc8a21ff9f54fce4258f18b19
01df6a8ee2