Simplify visitor marking mode tracking.

Simplify visitor marking mode tracking.

Move the marking mode to VisitorHelper<>, so that
both Visitor and InlinedGlobalMarkingVisitor can access
and reuse it.

In order to do so, hoist out Visitor::MarkingMode as an
enum class.

R=
BUG=

Review-Url: https://codereview.chromium.org/2625363002
Cr-Commit-Position: refs/heads/master@{#443444}
Committed: https://chromium.googlesource.com/chromium/src/+/e0bcd199795d70a6428d4b41860b2589a9c3652a

[sof, 2017-01-12 15:29:32]

The CQ bit was checked by sigbjornf@opera.com to run a CQ dry run

[commit-bot: I haz the power, 2017-01-12 15:29:54]

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

[sof, 2017-01-12 15:49:33]

The CQ bit was checked by sigbjornf@opera.com to run a CQ dry run

[commit-bot: I haz the power, 2017-01-12 15:49:52]

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, 2017-01-12 16:08:16]

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

[commit-bot: I haz the power, 2017-01-12 16:08:16]

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

[sof, 2017-01-12 16:10:21]

The CQ bit was checked by sigbjornf@opera.com to run a CQ dry run

[commit-bot: I haz the power, 2017-01-12 16:10:57]

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

[sof, 2017-01-12 16:12:38]

sigbjornf@opera.com changed reviewers:
+ oilpan-reviews@chromium.org

[sof, 2017-01-12 16:12:39]

please take a look.

[haraken, 2017-01-12 16:26:47]

LGTM

[commit-bot: I haz the power, 2017-01-12 20:27:01]

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

[commit-bot: I haz the power, 2017-01-12 20:27:02]

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_...)

[sof, 2017-01-12 21:59:00]

The CQ bit was checked by sigbjornf@opera.com

[commit-bot: I haz the power, 2017-01-12 21:59:30]

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, 2017-01-13 01:42:12]

CQ is committing da patch.

Bot data: {"patchset_id": 40001, "attempt_start_ts": 1484258340628240,
"parent_rev": "5294b308574741e970de525415d8aa59feb92345", "commit_rev":
"e0bcd199795d70a6428d4b41860b2589a9c3652a"}

[commit-bot: I haz the power, 2017-01-13 01:42:41]

Description was changed from

==========
Simplify visitor marking mode tracking.

Move the marking mode to VisitorHelper<>, so that
both Visitor and InlinedGlobalMarkingVisitor can access
and reuse it.

In order to do so, hoist out Visitor::MarkingMode as an
enum class.

R=
BUG=
==========

to

==========
Simplify visitor marking mode tracking.

Move the marking mode to VisitorHelper<>, so that
both Visitor and InlinedGlobalMarkingVisitor can access
and reuse it.

In order to do so, hoist out Visitor::MarkingMode as an
enum class.

R=
BUG=

Review-Url: https://codereview.chromium.org/2625363002
Cr-Commit-Position: refs/heads/master@{#443444}
Committed:
https://chromium.googlesource.com/chromium/src/+/e0bcd199795d70a6428d4b41860b...
==========

[commit-bot: I haz the power, 2017-01-13 01:42:43]

Committed patchset #3 (id:40001) as
https://chromium.googlesource.com/chromium/src/+/e0bcd199795d70a6428d4b41860b...