Make sure that the LockTaskUtilityActivityIfWhitelisted was started.

There is flaky in some device. After FallbackHome received the broadcast of USER_UNLOCKED, when the system was preparing to start LockTaskUtilityActivityIfWhitelisted, the case started the 'android.settings.SETTINGS', resulting in LockTaskUtilityActivityIfWhitelisted not being started.

Test: run cts -m CtsDevicePolicyManagerTestCases -t com.android.cts.devicepolicy.MixedProfileOwnerTest#testLockTaskAfterReboot_tryOpeningSettings

Bug: 146006729

Change-Id: I6db66d7de561f031ccd79738224f2cd4b9a05e34
Signed-off-by: duanyangqi <duanyangqi@xiaomi.com>
(cherry picked from commit 216ed1555b5f60ad048f503f985722fbf448a7f8)
2 files changed