Implement WTF::WeakPtr in terms of base::WeakPtr

Implement WTF::WeakPtr in terms of base::WeakPtr

BUG=none

Committed: https://crrev.com/288b352ea69e3cff2540ac701bb181485d423192
Cr-Commit-Position: refs/heads/master@{#416133}

[dcheng, 2016-08-31 22:20:18]

Description was changed from

==========
WeakPtr fun.

BUG=
==========

to

==========
WeakPtr fun.

BUG=
==========

[dcheng, 2016-08-31 22:27:51]

Description was changed from

==========
WeakPtr fun.

BUG=
==========

to

==========
Implement WTF::WeakPtr in terms of base::WeakPtr

BUG=none
==========

[dcheng, 2016-08-31 22:27:51]

dcheng@chromium.org changed reviewers:
+ esprehn@chromium.org

[dcheng, 2016-08-31 23:55:27]

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

[commit-bot: I haz the power, 2016-08-31 23:55:51]

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

[dcheng, 2016-08-31 23:56:27]

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

[commit-bot: I haz the power, 2016-08-31 23:56:54]

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, 2016-09-01 00:47:43]

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

[commit-bot: I haz the power, 2016-09-01 00:47:44]

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

[Charlie Harrison, 2016-09-01 18:48:15]

csharrison@chromium.org changed reviewers:
+ csharrison@chromium.org

[Charlie Harrison, 2016-09-01 18:48:16]

I think we either have to:
1. Destroy the bg parser on the main thread. 
2. Do something drastic w/ Persistent<MediaValuesCached>. Not sure what the best
approach here is but we could do something hacky like:
 - initialize it on the bg parser thread after construction
 - copy the values in an object not on the oilpan heap (seems not great). Maybe
the core data could be off heap and the main thread version could be a simple
on-heap wrapper.

just a few ideas.

[esprehn, 2016-09-01 18:59:27]

esprehn@chromium.org changed reviewers:
+ yoav@yoav.ws

[esprehn, 2016-09-01 18:59:48]

On 2016/09/01 at 18:48:16, csharrison wrote:
> I think we either have to:
> 1. Destroy the bg parser on the main thread. 
> 2. Do something drastic w/ Persistent<MediaValuesCached>. Not sure what the
best approach here is but we could do something hacky like:
>  - initialize it on the bg parser thread after construction
>  - copy the values in an object not on the oilpan heap (seems not great).
Maybe the core data could be off heap and the main thread version could be a
simple on-heap wrapper.
> 
> just a few ideas.

I really wan to get rid of this cross thread persistent that is
MediaValuesCached, it keeps biting us.

[dcheng, 2016-09-01 19:01:30]

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

[commit-bot: I haz the power, 2016-09-01 19:02:59]

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

[Charlie Harrison, 2016-09-01 19:17:16]

On 2016/09/01 18:59:48, esprehn wrote:
> On 2016/09/01 at 18:48:16, csharrison wrote:
> > I think we either have to:
> > 1. Destroy the bg parser on the main thread. 
> > 2. Do something drastic w/ Persistent<MediaValuesCached>. Not sure what the
> best approach here is but we could do something hacky like:
> >  - initialize it on the bg parser thread after construction
> >  - copy the values in an object not on the oilpan heap (seems not great).
> Maybe the core data could be off heap and the main thread version could be a
> simple on-heap wrapper.
> > 
> > just a few ideas.
> 
> I really wan to get rid of this cross thread persistent that is
> MediaValuesCached, it keeps biting us.

Agreed. I think I am most in favor of having it be a POD that is wrapped by
oilpan on the main thread but the bg parser just keeps a raw struct copy. WDYT?

[Charlie Harrison, 2016-09-01 19:25:31]

https://codereview.chromium.org/2300813003/diff/60001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/html/parser/HTMLDocumentParser.cpp (right):

https://codereview.chromium.org/2300813003/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/html/parser/HTMLDocumentParser.cpp:787:
postTaskToLookaheadParser(Synchronous, &BackgroundHTMLParser::init,
m_backgroundParser, document()->url(),
passed(CachedDocumentParameters::create(document())),
MediaValuesCached::MediaValuesCachedData(*document()));
This method is fine with me for now though to unblock this work. We should
definitely get rid of it long term though. Feel free to add a TODO(csharrison).

[dcheng, 2016-09-01 19:27:42]

This CL wasn't quite ready for review, but I guess everyone found it.

I'm happy to investigate other cleanups around the media values stuff, but if
the init() method is OK with everyone for now, it seems to be the 'cleanest'
way. Hopefully the trybots agree.

[dcheng, 2016-09-01 20:12:19]

OK, bots seem OK, so PTAL. I added a TODO per csharrison's suggestion.

[dcheng, 2016-09-01 20:12:21]

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

[commit-bot: I haz the power, 2016-09-01 20:13:07]

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

[Charlie Harrison, 2016-09-01 20:21:42]

It lgtm as long as esprehn is happy.

[esprehn, 2016-09-01 21:36:18]

lgtm

[commit-bot: I haz the power, 2016-09-01 22:25:10]

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

[commit-bot: I haz the power, 2016-09-01 22:25:11]

Dry run: Try jobs failed on following builders:
  win_chromium_rel_ng on master.tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_...)

[dcheng, 2016-09-01 22:25:16]

The CQ bit was unchecked by dcheng@chromium.org

[dcheng, 2016-09-01 22:25:16]

The CQ bit was checked by dcheng@chromium.org

[commit-bot: I haz the power, 2016-09-01 22:26:11]

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, 2016-09-02 00:00:15]

Description was changed from

==========
Implement WTF::WeakPtr in terms of base::WeakPtr

BUG=none
==========

to

==========
Implement WTF::WeakPtr in terms of base::WeakPtr

BUG=none
==========

[commit-bot: I haz the power, 2016-09-02 00:00:17]

Committed patchset #5 (id:80001)

[commit-bot: I haz the power, 2016-09-02 00:02:10]

Description was changed from

==========
Implement WTF::WeakPtr in terms of base::WeakPtr

BUG=none
==========

to

==========
Implement WTF::WeakPtr in terms of base::WeakPtr

BUG=none

Committed: https://crrev.com/288b352ea69e3cff2540ac701bb181485d423192
Cr-Commit-Position: refs/heads/master@{#416133}
==========

[commit-bot: I haz the power, 2016-09-02 00:02:11]

Patchset 5 (id:??) landed as
https://crrev.com/288b352ea69e3cff2540ac701bb181485d423192
Cr-Commit-Position: refs/heads/master@{#416133}

[hiroshige, 2016-09-07 02:06:48]

A revert of this CL (patchset #5 id:80001) has been created in
https://codereview.chromium.org/2318883002/ by hiroshige@chromium.org.

The reason for reverting is: Caused data races/crashes.

BUG=643777.