Toast: Fix the concurrency problem of mAuthenticator

In terms of calling logic, there is concurrency when mAuthenticator is assigned,
which causes the phone to restart. We need to add a lock to protect him.

Bug: 256398179

Test: atest AccountManagerServiceTest

Signed-off-by: hupeng3 <hp121520@gmail.com>
Change-Id: I937f6e00c0ac7cca76f26b37a365b5f19171eac6
1 file changed