[webkit-changes] [WebKit/WebKit] 2440e9: backface-visibility:hidden should create a stackin...

[mattwoodrow]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 2440e9efc74d6acbb62f9e024daa7f731e394759
      https://github.com/WebKit/WebKit/commit/2440e9efc74d6acbb62f9e024daa7f731e394759
  Author: Matt Woodrow <mattwoodrow at apple.com>
  Date:   2023-09-13 (Wed, 13 Sep 2023)

  Changed paths:
    M LayoutTests/TestExpectations
    A LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002-expected.html
    A LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002.html
    R LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002.tentative-expected.html
    R LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002.tentative.html
    A LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-003-expected.html
    M LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-003-ref.html
    A LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-003.html
    R LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-003.tentative-expected.html
    R LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-003.tentative.html
    A LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-004-expected.html
    A LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-004.html
    R LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-004.tentative-expected.html
    R LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-004.tentative.html
    A LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-005-expected.html
    A LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-005.html
    R LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-005.tentative-expected.html
    R LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-005.tentative.html
    R LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-animated-002-expected.html
    R LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-animated-002.html
    M Source/WTF/Scripts/Preferences/UnifiedWebPreferences.yaml
    M Source/WebCore/rendering/RenderBox.cpp
    M Source/WebCore/rendering/RenderBox.h
    M Source/WebCore/rendering/RenderLayer.cpp
    M Source/WebCore/style/StyleAdjuster.cpp

  Log Message:
  -----------
  backface-visibility:hidden should create a stacking context and containing block.
https://bugs.webkit.org/show_bug.cgi?id=261532
<rdar://114732608>

Reviewed by Simon Fraser.

As of https://github.com/w3c/csswg-drafts/pull/9348, backface-visibility:hidden should create a containing block and stacking context, if the element participates in a 3D rendering context.

This adds a new preference for this change (currently disabled, until other engines are ready to ship the change), and makes the code changes.

It also removes old WPTs that relied on the previous behaviour, and replaces them with new ones testing the new spec.

* LayoutTests/TestExpectations:
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002-expected.html: Copied from LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002.tentative-expected.html.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002.html: Renamed from LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002.tentative.html.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-003-expected.html: Copied from LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002.tentative-expected.html.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-003-ref.html:
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-003.html: Added.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-003.tentative-expected.html: Removed.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-003.tentative.html: Removed.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-004-expected.html: Copied from LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002.tentative-expected.html.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-004.html: Added.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-004.tentative-expected.html: Removed.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-004.tentative.html: Removed.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-005-expected.html: Renamed from LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-002.tentative-expected.html.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-005.html: Added.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-005.tentative-expected.html: Removed.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-005.tentative.html: Removed.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-animated-002-expected.html: Removed.
* LayoutTests/imported/w3c/web-platform-tests/css/css-transforms/backface-visibility-hidden-animated-002.html: Removed.
* Source/WTF/Scripts/Preferences/UnifiedWebPreferences.yaml:
* Source/WebCore/rendering/RenderBox.cpp:
(WebCore::RenderBox::updateFromStyle):
(WebCore::RenderBox::computeHasTransformRelatedProperty const):
* Source/WebCore/rendering/RenderBox.h:
* Source/WebCore/rendering/RenderLayer.cpp:
(WebCore::RenderLayer::clippingRootForPainting const):
* Source/WebCore/style/StyleAdjuster.cpp:
(WebCore::Style::Adjuster::adjust const):

Canonical link: https://commits.webkit.org/267980@main