[webkit-changes] [WebKit/WebKit] 0ab891: unionRect(const Vector<LayoutRect>&) behaves incor...

[Simon Fraser]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 0ab8911857862b8a5bada65ec96d83eb9eafefdc
      https://github.com/WebKit/WebKit/commit/0ab8911857862b8a5bada65ec96d83eb9eafefdc
  Author: Simon Fraser <simon.fraser at apple.com>
  Date:   2023-08-01 (Tue, 01 Aug 2023)

  Changed paths:
    M Source/WebCore/platform/graphics/LayoutRect.cpp

  Log Message:
  -----------
  unionRect(const Vector<LayoutRect>&) behaves incorrectly with empty rects
https://bugs.webkit.org/show_bug.cgi?id=259674
rdar://113183595

Reviewed by Alan Baradlay.

unionRect(const Vector<LayoutRect>&) behaves incorrectly if the input vector contains
a single zero-size rect with a non-zero location; it will union with the empty rect,
and therefore return the empty rect.

This is not known to change any behavior, but a future change in bug 259672
will exercise this code.

* Source/WebCore/platform/graphics/LayoutRect.cpp:
(WebCore::unionRect):

Canonical link: https://commits.webkit.org/266479@main