GitLab

Fix a few errors in the KeyRotationDeviceCloudPolicyTest.Basic browser
test - some of them were presumably causing the flakiness that led to
the test being disabled, some of them were accidentally added during
later refactorings:

1. Correctly pipe through LocalPolicyTestServerMixin the needed settings
   of policy_testserver: the usage of signing keys bundled into the
   Python server and the automatic rotation of the signing key with
   every policy request.
2. Fix misplaced calls in the test's SetUp() phase: everything needs to
   be done *before* calling the parent SetUp() in order to run before
   the test.
3. Make the test less fragile by doing two explicit fetches of policy
   inside the test body and checking that the key got rotated in
   between (instead of relying on the device policy stack making the
   first policy fetch during its initialization and on the right parity
   of the PolicyBuilder's policy key version).

Bug: 900631
Test: run the test 10'000 times (browser_tests --gtest_filter="KeyRotationDeviceCloudPolicyTest.Basic")
Change-Id: I5eaa4f6e03a54dcc26319d39323f5edf51904c65
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1829383
Commit-Queue: Maksim Ivanov <emaxx@chromium.org>
Reviewed-by: Denis Kuznetsov <antrim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#702976}