The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2f2ee2ca56a96188d516688f60b7988e9caee432

commit 2f2ee2ca56a96188d516688f60b7988e9caee432
Author: Abhishek Bhardwaj <abhishekbh@chromium.org>
Date: Thu Dec 20 23:44:22 2018

WakeLock: Remove separate wake lock class used in tests

This change removes a separate test implementation of wake locks. This
results in more production code being unit tested.

BUG=chromium:913353
TEST=Run WakeLockTest unit tests.

Change-Id: Ie4b3d3384c148c90c6ee937b91710bfe9b87d9c8
Reviewed-on: https://chromium-review.googlesource.com/c/1379704
Commit-Queue: Abhishek Bhardwaj <abhishekbh@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#618381}
[modify] https://crrev.com/2f2ee2ca56a96188d516688f60b7988e9caee432/services/device/wake_lock/BUILD.gn
[modify] https://crrev.com/2f2ee2ca56a96188d516688f60b7988e9caee432/services/device/wake_lock/wake_lock.cc
[modify] https://crrev.com/2f2ee2ca56a96188d516688f60b7988e9caee432/services/device/wake_lock/wake_lock.h
[modify] https://crrev.com/2f2ee2ca56a96188d516688f60b7988e9caee432/services/device/wake_lock/wake_lock_context.cc
[delete] https://crrev.com/a0cd397aee006d848319e8f7aea5b3f3e1b5a267/services/device/wake_lock/wake_lock_for_testing.cc
[delete] https://crrev.com/a0cd397aee006d848319e8f7aea5b3f3e1b5a267/services/device/wake_lock/wake_lock_for_testing.h
[modify] https://crrev.com/2f2ee2ca56a96188d516688f60b7988e9caee432/services/device/wake_lock/wake_lock_provider.cc
[modify] https://crrev.com/2f2ee2ca56a96188d516688f60b7988e9caee432/services/device/wake_lock/wake_lock_provider.h
[modify] https://crrev.com/2f2ee2ca56a96188d516688f60b7988e9caee432/services/device/wake_lock/wake_lock_unittest.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9a764cdd599968688a588f0fa4eaf5771b944b88

commit 9a764cdd599968688a588f0fa4eaf5771b944b88
Author: Abhishek Bhardwaj <abhishekbh@chromium.org>
Date: Fri Dec 21 02:19:32 2018

WakeLock: Add observer API for wake lock implementation

This change adds an observer API on the wake lock implementation class.
It notifies observers on wake lock acquisition and release. This API will
be used by the wake lock provider class to keep track of all wake locks
created by different clients.

BUG=chromium:913353
TEST=Dark resume controller unit tests.

Change-Id: I1195050e47b81ed463fa6cd5455ea5b6f960becd
Reviewed-on: https://chromium-review.googlesource.com/c/1372219
Commit-Queue: Abhishek Bhardwaj <abhishekbh@chromium.org>
Reviewed-by: Dan Erat <derat@chromium.org>
Reviewed-by: Ken Rockot <rockot@google.com>
Cr-Commit-Position: refs/heads/master@{#618432}
[modify] https://crrev.com/9a764cdd599968688a588f0fa4eaf5771b944b88/services/device/public/cpp/test/test_wake_lock_provider.cc
[modify] https://crrev.com/9a764cdd599968688a588f0fa4eaf5771b944b88/services/device/public/cpp/test/test_wake_lock_provider.h
[modify] https://crrev.com/9a764cdd599968688a588f0fa4eaf5771b944b88/services/device/wake_lock/wake_lock.cc
[modify] https://crrev.com/9a764cdd599968688a588f0fa4eaf5771b944b88/services/device/wake_lock/wake_lock.h

Setting defect without priority to default.