tree c442a3ed386ae1623defd9647c6f81e65c3db8f4
parent 9cad266457c59e8330c830c369784764b36386c1
author Tianjie Xu <xunchang@google.com> 1570577559 -0700
committer Tianjie Xu <xunchang@google.com> 1571188529 -0700

Allow update engine read public keys from otacerts.zip

The android build system installs both otacerts.zip and
update-payload-key.pub.pem on the device. And the latter is
converted from the X509 certificates inside the otacerts.zip
during the build time.

We can consolidate these two by letting update engine to parse
the public keys from otacerts.zip directly. This also allows
update engine to use multiple keys to verify the payload.

Bug: 116660991
Test: unittests pass
Change-Id: I0a499405f2835e1ff8b7916452cb3123046306a7