[CSS OM] StyledElementInlineStylePropertyMap creates a Ref cycle with its owner element

[Ryosuke Niwa]

There is a very obvious leak here.
StyledElementInlineStylePropertyMap ref's its element and Element Ref's the map in ElementRareData.

<rdar://problem/47254121>

[Ryosuke Niwa]

Created attachment 365308 [details]
Fixes the bug

[Ryosuke Niwa]

Created attachment 365309 [details]
Updated the change log

[Simon Fraser (smfr)]

Comment on attachment 365309 [details]
Updated the change log

View in context: https://bugs.webkit.org/attachment.cgi?id=365309&action=review

> Source/WebCore/dom/Element.cpp:209
> +        if (auto* map = elementRareData()->attributeStyleMap())
> +            map->clearElement();

Maybe ElementRareData should have a clearElement or clearNdoe function on it

[Ryosuke Niwa]

(In reply to Simon Fraser (smfr) from comment #3)
> Comment on attachment 365309 [details]
> Updated the change log
> 
> View in context:
> https://bugs.webkit.org/attachment.cgi?id=365309&action=review
> 
> > Source/WebCore/dom/Element.cpp:209
> > +        if (auto* map = elementRareData()->attributeStyleMap())
> > +            map->clearElement();
> 
> Maybe ElementRareData should have a clearElement or clearNdoe function on it

That approach makes sense as well. Although I'm hoping that I can just add the support for WeakPtr<Element> and remove this code.

[Ryosuke Niwa]

Committed r243239: <https://trac.webkit.org/changeset/243239>