Bug 228693 – Calling unobserve on ResizeObserver should not clear existing observations in active targets

• Status: RESOLVED
• Resolution: FIXED
• Component: DOM

[Ryosuke Niwa]

According to the spec https://drafts.csswg.org/resize-observer/#dom-resizeobserver-unobserve,
we should not be clearing the active targets when unobserve is called.

[Ryosuke Niwa]

Looks like Chrome has the same bug so that's a bit concerning...

[Ryosuke Niwa]

Created attachment 434729 [details]
Patch

[Chris Dumez]

Comment on attachment 434729 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=434729&action=review

r=me with changelog fix.

> LayoutTests/ChangeLog:13
> [phone]  Ryosuke Niwa  <[e-mail]>

double change log.

[Ryosuke Niwa]

Comment on attachment 434729 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=434729&action=review

>> LayoutTests/ChangeLog:13
>> [phone]  Ryosuke Niwa  <[e-mail]>
> 
> double change log.

Weird. Not sure what happened here. Will fix before landing.

[Ryosuke Niwa]

Committed r280551 (240178@main): <https://commits.webkit.org/240178@main>

[Radar WebKit Bug Importer]

<rdar://problem/81425446>

[Aleksandar Totic]

This might be a spec misunderstanding:

From the spec:

[[activeTargets]] represents all Elements whose size has changed since last observation broadcast that are eligible for broadcast.

What makes an element eligible is not explicitly defined. 
My intuition is that calling "unobserve" on an elment should make it inelligible.

[Aleksandar Totic]

Filed spec bug: https://github.com/w3c/csswg-drafts/issues/6493