tree 5b014598d5570900ddaf4cf6b240fd5aae1537db
parent 53496f6fb35ab0c9b1ebedace2c05e92ca86dc66
author Kevin Chyn <kchyn@google.com> 1563482243 -0700
committer Kevin Chyn <kchyn@google.com> 1563482661 -0700

Biometric HAL death should invoke handleError on the handler

All client lifecycle is modified on the handler. When the HAL dies,
serviceDied comes in on the main thread and will race with the rest of
client lifecycle manipulation. We need to guarantee this is in order,
otherwise it's possible for BiometricService to receive the following
order of events
1) BiometricService requests auth
2) Face/FingerprintService is ready to start auth
3) HAL dies in the middle of 2), and sends onError to BiometricService
4) onReadyForAuthentication is sent to BiometricService, causing NPE

With this change, it will guarantee that 3) occurs after 4), which will
avoid A) BiometricService receiving events out of order, and more
importantly B) allow BiometricPrompt to show the HW_UNAVAILABLE error
instead of crashing system server.

Fixes: 137800315

Test: Authentication with BiometricPromptDemo while killing the HAL
Change-Id: Iae2d5b39dd494123f274b47edcc44c3afc1fff8c