Use TaskScheduler instead of WorkerPool in cache_util.cc.

Use TaskScheduler instead of WorkerPool in cache_util.cc.

The following traits are used:

Priority: BACKGROUND
  User won't notice if this task takes an arbitrarily long time
  to complete.

Shutdown behavior: CONTINUE_ON_SHUTDOWN
  Tasks posted with this mode which have not started executing before
  shutdown is initiated will never run. Tasks with this mode running at
  shutdown will be ignored (the worker will not be joined).

  Note: Tasks that were previously posted to base::WorkerPool should
  use this shutdown behavior because this is how base::WorkerPool
  handles all its tasks.

May Block:
  Tasks posted with MayBlock() may block. This includes but is not
  limited to tasks that wait on synchronous file I/O operations:
  read or write a file from disk, interact with a pipe or a socket,
  rename or delete a file, enumerate files in a directory, etc. This
  trait isn't required for the mere use of locks.

BUG=659191
Review-Url: https://codereview.chromium.org/2610503002
Cr-Commit-Position: refs/heads/master@{#442985}
Committed: https://chromium.googlesource.com/chromium/src/+/8d1a5a1e352ee6b2aee40b42d9fdc4b6e0c97fed

[fdoray, 2017-01-01 23:10:26]

The CQ bit was checked by fdoray@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-01 23:10:42]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-01-01 23:16:09]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-01-01 23:16:10]

Dry run: Try jobs failed on following builders:
  android_cronet on master.tryserver.chromium.android (JOB_FAILED,
https://build.chromium.org/p/tryserver.chromium.android/builders/android_cron...)
  ios-device-xcode-clang on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-device-xcode-...)
  ios-simulator-xcode-clang on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator-xco...)

[fdoray, 2017-01-04 17:05:31]

The CQ bit was checked by fdoray@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-04 17:05:43]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-01-04 17:43:36]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-01-04 17:43:37]

Dry run: Try jobs failed on following builders:
  cast_shell_linux on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/cast_shell_linu...)

[fdoray, 2017-01-09 17:00:49]

The CQ bit was checked by fdoray@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2017-01-09 17:01:18]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-01-09 18:03:37]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2017-01-09 18:03:37]

Dry run: This issue passed the CQ dry run.

[fdoray, 2017-01-09 21:17:54]

fdoray@chromium.org changed reviewers:
+ gavinp@chromium.org

[fdoray, 2017-01-09 21:17:55]

PTAL

[gavinp, 2017-01-11 18:32:39]

lgtm

[fdoray, 2017-01-11 18:34:33]

The CQ bit was checked by fdoray@chromium.org

[commit-bot: I haz the power, 2017-01-11 18:35:12]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-01-11 19:45:41]

CQ is committing da patch.

Bot data: {"patchset_id": 40001, "attempt_start_ts": 1484159673897530,
"parent_rev": "6c267ca6a4bc8f207d58a682a4c98f0b9b697ad4", "commit_rev":
"8d1a5a1e352ee6b2aee40b42d9fdc4b6e0c97fed"}

[commit-bot: I haz the power, 2017-01-11 19:46:09]

Description was changed from

==========
Use TaskScheduler instead of WorkerPool in cache_util.cc.

The following traits are used:

Priority: BACKGROUND
  User won't notice if this task takes an arbitrarily long time
  to complete.

Shutdown behavior: CONTINUE_ON_SHUTDOWN
  Tasks posted with this mode which have not started executing before
  shutdown is initiated will never run. Tasks with this mode running at
  shutdown will be ignored (the worker will not be joined).

  Note: Tasks that were previously posted to base::WorkerPool should
  use this shutdown behavior because this is how base::WorkerPool
  handles all its tasks.

May Block:
  Tasks posted with MayBlock() may block. This includes but is not
  limited to tasks that wait on synchronous file I/O operations:
  read or write a file from disk, interact with a pipe or a socket,
  rename or delete a file, enumerate files in a directory, etc. This
  trait isn't required for the mere use of locks.

BUG=659191
==========

to

==========
Use TaskScheduler instead of WorkerPool in cache_util.cc.

The following traits are used:

Priority: BACKGROUND
  User won't notice if this task takes an arbitrarily long time
  to complete.

Shutdown behavior: CONTINUE_ON_SHUTDOWN
  Tasks posted with this mode which have not started executing before
  shutdown is initiated will never run. Tasks with this mode running at
  shutdown will be ignored (the worker will not be joined).

  Note: Tasks that were previously posted to base::WorkerPool should
  use this shutdown behavior because this is how base::WorkerPool
  handles all its tasks.

May Block:
  Tasks posted with MayBlock() may block. This includes but is not
  limited to tasks that wait on synchronous file I/O operations:
  read or write a file from disk, interact with a pipe or a socket,
  rename or delete a file, enumerate files in a directory, etc. This
  trait isn't required for the mere use of locks.

BUG=659191

Review-Url: https://codereview.chromium.org/2610503002
Cr-Commit-Position: refs/heads/master@{#442985}
Committed:
https://chromium.googlesource.com/chromium/src/+/8d1a5a1e352ee6b2aee40b42d9fd...
==========

[commit-bot: I haz the power, 2017-01-11 19:46:10]

Committed patchset #3 (id:40001) as
https://chromium.googlesource.com/chromium/src/+/8d1a5a1e352ee6b2aee40b42d9fd...

[mikecase (-- gone --), 2017-01-11 22:11:53]

A revert of this CL (patchset #3 id:40001) has been created in
https://codereview.chromium.org/2624073004/ by mikecase@chromium.org.

The reason for reverting is: suspect for net_unittest failures.

[dschuyler, 2017-01-11 22:12:06]

A revert of this CL (patchset #3 id:40001) has been created in
https://codereview.chromium.org/2626163002/ by dschuyler@chromium.org.

The reason for reverting is: It looks like this CL may be related to a unit test
failure on this build:
https://build.chromium.org/p/chromium.win/builders/Win10%20Tests%20x64/builds...
- Sheriff.