Remove 'presentational hints' from width attribute for <hr>

https://bugs.webkit.org/show_bug.cgi?id=274605

Reviewed by Ryosuke Niwa.

This patch aligns WebKit with Gecko / Firefox and web specification [1]:

[1] https://html.spec.whatwg.org/#the-hr-element-2

"The width attribute on an hr element maps to the dimension property 'width' on the element."

As per above, there should not be any presentational hints'. Hence, this
patch removes them from WebKit's codebase.

* Source/WebCore/html/HTMLHRElement.cpp:
(WebCore::HTMLHRElement::collectPresentationalHintsForAttribute):
* LayoutTests/imported/w3c/web-platform-tests/html/rendering/dimension-attributes-expected.txt: Rebaseline

Canonical link: https://commits.webkit.org/279245@main

LayoutTests/imported/w3c/web-platform-tests/html/rendering/dimension-attributes-expected.txt

@@ -16,10 +16,10 @@ PASS <hr width="200.%"> mapping to width
 PASS <hr width="20.25e2"> mapping to width
 PASS <hr width="20.25E2"> mapping to width
 PASS <hr width="0"> mapping to width
-FAIL <hr width="0%"> mapping to width assert_equals: expected "0%" but got "0px"
+PASS <hr width="0%"> mapping to width
 PASS <hr width="0px"> mapping to width
-FAIL <hr width="-0"> mapping to width assert_equals: expected "auto" but got "0px"
-FAIL <hr width="-0%"> mapping to width assert_equals: expected "auto" but got "0px"
+PASS <hr width="-0"> mapping to width
+PASS <hr width="-0%"> mapping to width
 PASS <hr width="-200"> mapping to width
 PASS <hr width="-200px"> mapping to width
 PASS <hr width="   -200"> mapping to width
@@ -32,8 +32,8 @@ PASS <hr width="   +200.25in    "> mapping to width
 PASS <hr width="+200%"> mapping to width
 PASS <hr width="   +200.25%    "> mapping to width
 PASS <hr width="   +200.25%abc"> mapping to width
-FAIL <hr width="+0"> mapping to width assert_equals: expected "auto" but got "0px"
-FAIL <hr width="+0%"> mapping to width assert_equals: expected "auto" but got "0px"
+PASS <hr width="+0"> mapping to width
+PASS <hr width="+0%"> mapping to width
 PASS <hr width="."> mapping to width
 PASS <hr width=".%"> mapping to width
 PASS <hr width=".x"> mapping to width

Source/WebCore/html/HTMLHRElement.cpp

@@ -1,7 +1,7 @@
 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
- * Copyright (C) 2003, 2010 Apple Inc. All rights reserved.
+ * Copyright (C) 2003-2024 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ -85,10 +85,7 @@ void HTMLHRElement::collectPresentationalHintsForAttribute(const QualifiedName&
         }
         break;
     case AttributeNames::widthAttr:
-        if (auto valueInteger = parseHTMLInteger(value); valueInteger && !*valueInteger)
-            addPropertyToPresentationalHintStyle(style, CSSPropertyWidth, 0, CSSUnitType::CSS_PX);
-        else
-            addHTMLLengthToStyle(style, CSSPropertyWidth, value);
+        addHTMLLengthToStyle(style, CSSPropertyWidth, value);
         break;
     case AttributeNames::colorAttr:
         addPropertyToPresentationalHintStyle(style, CSSPropertyBorderStyle, CSSValueSolid);