Non-Oilpan Memory: Fix HTMLViewSourceDocument and WebLeakDetector.

Non-Oilpan Memory: Fix HTMLViewSourceDocument and WebLeakDetector.

1) RenderViewImplTest.DidFailProvisionalLoadWithErrorForCancellation test was leaking with HTMLViewSourceDocument.
2) V8PerIsolateData::from(isolate)->ensureScriptRegexpContext() was leaking in WebLeakDetectorImpl::collectGarbageAndGetDOMCounts
because of cycle.

This is required by chromium part:
https://codereview.chromium.org/1363523002

BUG=506433
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=202624

[loyso (OOO), 2015-09-22 04:40:40]

loyso@chromium.org changed reviewers:
+ haraken@chromium.org, sigbjornf@opera.com, tkent@chromium.org

[loyso (OOO), 2015-09-22 04:46:46]

loyso@chromium.org changed reviewers:
- tkent@chromium.org

[loyso (OOO), 2015-09-22 04:58:22]

loyso@chromium.org changed reviewers:
+ thakis@chromium.org

[haraken, 2015-09-22 06:19:33]

LGTM

[loyso (OOO), 2015-09-22 06:22:03]

The CQ bit was checked by loyso@chromium.org

[commit-bot: I haz the power, 2015-09-22 06:22:06]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1360723003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1360723003/1

[sof, 2015-09-22 06:50:41]

sigbjornf@opera.com changed reviewers:
+ hajimehoshi@chromium.org

[sof, 2015-09-22 06:50:41]

+hajimehoshi for the ScriptRegexpContext part.

lgtm also.

[commit-bot: I haz the power, 2015-09-22 08:03:46]

Committed patchset #1 (id:1) as
https://src.chromium.org/viewvc/blink?view=rev&revision=202624