Auto-sizes: Align CSS rule with Google Chrome implementation

[mukeshpanchal27]

Trac ticket: https://core.trac.wordpress.org/ticket/62515

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[github-actions]

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[mukeshpanchal27]

These PR update core CSS to align with Google Chrome implementation. In most issue the sites uses height:auto CSS rules so it will stretch to 1500px per CSS that implemented through PR #7813.

Per https://issues.chromium.org/issues/352077687#comment5, either we should pass the height & width for image or it will load 300X150 dimensions.

This is working as intended based on the spec definition for sizes="auto"

The user agent stylesheet change is based on the rendering section of the html spec:
https://html.spec.whatwg.org/#img-contain-size

The following note is present in the spec:
"In addition, it is strongly encouraged to specify dimensions using the width and height attributes or with CSS. Without specified dimensions, the image will likely render with 300x150 dimensions because sizes="auto" implies contain-intrinsic-size: 300px 150px in the Rendering section."
https://html.spec.whatwg.org/#sizes-attributes

Specifying the images dimensions should work around this problem.

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Props mukesh27, flixos90, joemcgill.

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[felixarntz]

@mukeshpanchal27 This is not a proper fix, as it breaks the behavior again that this is fixing in the first place.

We must not use exactly what Google Chrome uses, because that's precisely what caused the other bug.

[joemcgill]

Thanks @mukeshpanchal27, but the dimensions added here were intentionally made larger than the default UA stylesheet in Chrome in #7813.

I'd suggest closing this PR.

[mukeshpanchal27]

@mukeshpanchal27 This is not a proper fix, as it breaks the behavior again that this is fixing in the first place.

We must not use exactly what Google Chrome uses, because that's precisely what caused the other bug.

Thanks for review. As a side effect how we solve the height issue for image as chrome return 150px and WP core return 1500px?

[mukeshpanchal27]

Closing as it re-introduce original issue reported at https://core.trac.wordpress.org/ticket/62413