[webkit-changes] [WebKit/WebKit] b10e15: Fix negative shadow repaint issue

[Ahmad Saleem]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: b10e15662611c4b0b0ff17864d07310efdc39dda
      https://github.com/WebKit/WebKit/commit/b10e15662611c4b0b0ff17864d07310efdc39dda
  Author: Ahmad Saleem <ahmad.saleem792+github at gmail.com>
  Date:   2023-01-27 (Fri, 27 Jan 2023)

  Changed paths:
    A LayoutTests/fast/box-shadow/negative-shadow-box-expand-expected.txt
    A LayoutTests/fast/box-shadow/negative-shadow-box-expand.html
    A LayoutTests/fast/box-shadow/negative-shadow-box-shrink-expected.txt
    A LayoutTests/fast/box-shadow/negative-shadow-box-shrink.html
    M Source/WebCore/rendering/RenderElement.cpp

  Log Message:
  -----------
  Fix negative shadow repaint issue

Fix negative shadow repaint issue
https://bugs.webkit.org/show_bug.cgi?id=251176

Reviewed by Simon Fraser.

Merge - https://src.chromium.org/viewvc/blink?view=revision&revision=164709

When a box with negative v-shadow changes height, the repaint rect
is inadequate resulting some part of shadow is not repainted.
Fix the issue by considering negative shadow-top/shadow-left.

* Source/WebCore/rendering/RenderElement.cpp:
(RenderElement::repaintAfterLayout): Add consideration for negative shadows
* LayoutTests/fast/box-shadow/negative-shadow-box-shrink.html: Add Test Case
* LayoutTests/fast/box-shadow/negative-shadow-box-shrink-expected.txt: Add Test Case Expectation
* LayoutTests/fast/box-shadow/negative-shadow-box-expand.html: Add Test Case
* LayoutTests/fast/box-shadow/negative-shadow-box-shrink-expand.txt: Add Test Case Expectation

Canonical link: https://commits.webkit.org/259497@main