Add support for postNonNestableIdleTask to the Scheduler and use it in Oilpan

Add support for postNonNestableIdleTask to the Scheduler and use it in Oilpan

Adds postNonNestableIdleTask functionality to the Scheduler and modifies
Oilpan's idle GC task to be posted as non-nestable idle tasks.  This guarantees
that there will be no heap pointers on the stack when Oilpan's idle GC task is run
and enables the GC to be precise instead of conservative.

Chromium side of patch: https://codereview.chromium.org/970473004/

BUG=455713
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=191906

[rmcilroy, 2015-03-03 19:34:58]

rmcilroy@chromium.org changed reviewers:
+ haraken@chromium.org, kouhei@chromium.org, skyostil@chromium.org

[rmcilroy, 2015-03-03 19:34:59]

haraken / kouhei@: Could you please take a look at the Oilpan change.

skyostil@: Could you please take a look at the scheduler changes.

Thanks.

[haraken, 2015-03-04 01:15:09]

LGTM

Do you know a way to check that we're not in a nested event loop? If there is an
API to check it, I want to insert a couple of ASSERTs to heap/.

[kouhei (in TOK), 2015-03-04 01:15:21]

Yay! Thanks for adding support for this.

lgtm

[Sami, 2015-03-04 11:01:01]

lgtm, thanks Ross!

On 2015/03/04 01:15:09, haraken wrote:
> Do you know a way to check that we're not in a nested event loop? If there is
an
> API to check it, I want to insert a couple of ASSERTs to heap/.

I don't think there's an API for querying that at the moment, but perhaps we
could add some tracking here (I don't know for sure this gets called in all
nesting cases):

https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit...

[rmcilroy, 2015-03-13 22:51:32]

On 2015/03/04 01:15:09, haraken wrote:
> LGTM
> 
> Do you know a way to check that we're not in a nested event loop? If there is
an
> API to check it, I want to insert a couple of ASSERTs to heap/.

Sorry, thought I'd replied to this. In  chromium you could do:
DCHECK(!base::MessageLoop::current()->IsNested())
But I don't think this API is exposed to Blink so it would take some plumbing.

[rmcilroy, 2015-03-13 22:51:37]

The CQ bit was checked by rmcilroy@chromium.org

[commit-bot: I haz the power, 2015-03-13 22:51:55]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/976723002/1

[commit-bot: I haz the power, 2015-03-13 22:57:21]

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

[commit-bot: I haz the power, 2015-03-13 22:57:22]

Try jobs failed on following builders:
  android_blink_compile_rel on tryserver.blink (JOB_FAILED,
http://build.chromium.org/p/tryserver.blink/builders/android_blink_compile_re...)

[rmcilroy, 2015-03-16 09:33:23]

The CQ bit was checked by rmcilroy@chromium.org

[rmcilroy, 2015-03-16 09:33:23]

The patchset sent to the CQ was uploaded after l-g-t-m from
haraken@chromium.org, skyostil@chromium.org, kouhei@chromium.org
Link to the patchset: https://codereview.chromium.org/976723002/#ps20001 (title:
"Rebased")

[commit-bot: I haz the power, 2015-03-16 09:33:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/976723002/20001

[commit-bot: I haz the power, 2015-03-16 09:50:28]

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

[commit-bot: I haz the power, 2015-03-16 09:50:28]

Try jobs failed on following builders:
  blink_presubmit on tryserver.blink (JOB_FAILED,
http://build.chromium.org/p/tryserver.blink/builders/blink_presubmit/builds/2...)

[rmcilroy, 2015-03-16 10:46:52]

rmcilroy@chromium.org changed reviewers:
+ jochen@chromium.org

[rmcilroy, 2015-03-16 10:46:53]

jochen@chromium.org: Please review changes in public/platform/WebScheduler.h,
thanks!

[jochen (gone - plz use gerrit), 2015-03-16 10:48:27]

lgtm

[rmcilroy, 2015-03-16 10:49:14]

The CQ bit was checked by rmcilroy@chromium.org

[commit-bot: I haz the power, 2015-03-16 10:49:37]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/976723002/20001

[commit-bot: I haz the power, 2015-03-16 11:09:02]

Committed patchset #2 (id:20001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=191906