Replace deprecated base::NonThreadSafe in chrome/browser/prerender in favor of SequenceChecker.

Replace deprecated base::NonThreadSafe in chrome/browser/prerender in favor of SequenceChecker.

Note to crash team: This CL is a refactor and has no intended behavior change.

This change was scripted by https://crbug.com/676387#c8.

Note-worthy for the reviewer:
 * SequenceChecker enforces thread-safety but not thread-affinity!
   If the classes that were updated are thread-affine (use thread local
   storage or a third-party API that does) they should be migrated to
   ThreadChecker instead.
 * ~NonThreadSafe() used to implcitly check in its destructor
   ~Sequence/ThreadChecker() doesn't by design. To keep this CL a
   no-op, an explicit check was added to the destructor of migrated
   classes.
 * NonThreadSafe used to provide access to subclasses, as such
   the |sequence_checker_| member was made protected rather than
   private where necessary.

BUG=676387
This CL was uploaded by git cl split.

R=davidben@chromium.org

Review-Url: https://codereview.chromium.org/2909193002
Cr-Commit-Position: refs/heads/master@{#475556}
Committed: https://chromium.googlesource.com/chromium/src/+/e78de22c51a073429e5cfdbebd74809cd4aaa3e7

[gab, 2017-05-30 02:43:58]

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

[gab, 2017-05-30 02:44:00]

Hi, this is an automated change made by https://crbug.com/676387#c8 and sharded
across directories for OWNERS.

No human has looked at this specific output yet, see cl description for things
to watch for.

If it LGTY, please CQ.

If it didn't pass CQ dry-run it may be a simple patch failure or an IWYU failure
from having this being a partial CL... please review anyways and a human will
look at the failure (and ping for re-review if anything major is required..). It
is known to compile all targets on Windows at r474679...  manual tweaks will
likely be required to smoothen things off, bear with me!

Thanks!
Gab

[commit-bot: I haz the power, 2017-05-30 02:44:56]

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, 2017-05-30 03:44:58]

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

[commit-bot: I haz the power, 2017-05-30 03:44:59]

Dry run: This issue passed the CQ dry run.

[davidben, 2017-05-30 16:40:42]

The CQ bit was checked by davidben@chromium.org

[davidben, 2017-05-30 16:40:42]

lgtm

[commit-bot: I haz the power, 2017-05-30 16:41:08]

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, 2017-05-30 16:45:47]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1496162442297750, "parent_rev":
"a58f83c9a322313b6aa2dbcfe968f8733731db29", "commit_rev":
"e78de22c51a073429e5cfdbebd74809cd4aaa3e7"}

[commit-bot: I haz the power, 2017-05-30 16:45:54]

Description was changed from

==========
Replace deprecated base::NonThreadSafe in chrome/browser/prerender in favor of
SequenceChecker.

Note to crash team: This CL is a refactor and has no intended behavior change.

This change was scripted by https://crbug.com/676387#c8.

Note-worthy for the reviewer:
 * SequenceChecker enforces thread-safety but not thread-affinity!
   If the classes that were updated are thread-affine (use thread local
   storage or a third-party API that does) they should be migrated to
   ThreadChecker instead.
 * ~NonThreadSafe() used to implcitly check in its destructor
   ~Sequence/ThreadChecker() doesn't by design. To keep this CL a
   no-op, an explicit check was added to the destructor of migrated
   classes.
 * NonThreadSafe used to provide access to subclasses, as such
   the |sequence_checker_| member was made protected rather than
   private where necessary.

BUG=676387
This CL was uploaded by git cl split.

R=davidben@chromium.org
==========

to

==========
Replace deprecated base::NonThreadSafe in chrome/browser/prerender in favor of
SequenceChecker.

Note to crash team: This CL is a refactor and has no intended behavior change.

This change was scripted by https://crbug.com/676387#c8.

Note-worthy for the reviewer:
 * SequenceChecker enforces thread-safety but not thread-affinity!
   If the classes that were updated are thread-affine (use thread local
   storage or a third-party API that does) they should be migrated to
   ThreadChecker instead.
 * ~NonThreadSafe() used to implcitly check in its destructor
   ~Sequence/ThreadChecker() doesn't by design. To keep this CL a
   no-op, an explicit check was added to the destructor of migrated
   classes.
 * NonThreadSafe used to provide access to subclasses, as such
   the |sequence_checker_| member was made protected rather than
   private where necessary.

BUG=676387
This CL was uploaded by git cl split.

R=davidben@chromium.org

Review-Url: https://codereview.chromium.org/2909193002
Cr-Commit-Position: refs/heads/master@{#475556}
Committed:
https://chromium.googlesource.com/chromium/src/+/e78de22c51a073429e5cfdbebd74...
==========

[commit-bot: I haz the power, 2017-05-30 16:45:54]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/chromium/src/+/e78de22c51a073429e5cfdbebd74...