Bug 989974 - Disable intermittent failing unit test, system/HardwareButtons press and release sleep (screen enabled)
Bug 864178 - [TestAgent] Run each test in its own sandbox r=julienw
Revert (manually revert) "Bug 933035 - [B2G][System][Lockscreen] The
phone goes to sleep on the lockscreen even though screen timeout is set
to never", which seems caused the Bug 980559.

    This reverts commit d808643fb7fca3fe6ffd1e415c135fe2d482e7df.
Merge pull request #17720 from KevinGrandon/bug_864178_test_agent_sandboxing

Bug 864178 - [TestAgent] Run each test in its own sandbox