[CSS Container Queries][Style queries] Resolve container units in sty…

…le queries correctly

https://bugs.webkit.org/show_bug.cgi?id=270511
rdar://124058441

Reviewed by Antoine Quint.

* LayoutTests/imported/w3c/web-platform-tests/css/css-contain/container-queries/custom-property-style-queries-expected.txt:
* Source/WebCore/css/query/ContainerQueryFeatures.cpp:

Provide the context element so container units can be resolved.

Canonical link: https://commits.webkit.org/275689@main

LayoutTests/imported/w3c/web-platform-tests/css/css-contain/container-queries/custom-property-style-queries-expected.txt

@@ -67,7 +67,7 @@ PASS Match registered <length> custom property with px.
 PASS Match registered <length> custom property with px via initial keyword.
 PASS Match registered <length> custom property with em in query.
 PASS Match registered <length> custom property with em in computed value.
-FAIL Match registered <length> custom property with cqi unit. assert_equals: expected "rgb(0, 128, 0)" but got "rgb(0, 0, 0)"
+PASS Match registered <length> custom property with cqi unit.
 PASS Match registered <length> custom property with initial value.
 PASS Match registered <length> custom property with initial value via initial keyword.
 PASS Should only match exact string for numbers in non-registered custom properties

Source/WebCore/css/query/ContainerQueryFeatures.cpp

@@ -189,7 +189,7 @@ struct StyleFeatureSchema : public FeatureSchema {
                 context.document.get(),
                 *context.conversionData.parentStyle(),
                 context.conversionData.rootStyle(),
-                nullptr
+                context.conversionData.elementForContainerUnitResolution()
             };
 
             auto dummyStyle = RenderStyle::clone(style);