[pointer_interceptor] Shadow dom tweaks

[ditman]

Change the pointer_interceptor so that it works better with the new slots way of embedding HtmlElementViews in flutter web master.

Related to: flutter/flutter#80524

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[stuartmorgan-g]

LGTM with a couple of questions.

[stuartmorgan-g]

Is this change fine for stable as well? (If not, you could always update the Flutter SDK requirement so Flutter 2.2 won't versions that have this change.)

[ditman]

Yes, thanks for asking. I tested this both with stable and master, manually and with the driver tests.

This is backwards compatible, it's just that there's many ways to "cover a parent div" with CSS, but in the engine we only check "are style.width and style.height set (to any value?) else: warn user".

This code is to disable that warning from our own packages.

[abnerh69]

Is this chat still opened? I am trying to avoid reload of iframe url using master/stable channel but can't make it works with slot like you said. Please, help!

[stuartmorgan-g]

@abnerh69 Please don't spam PRs for help. PRs are for discussing the specific PR, nothing else.