canvas-as-container-005.html & canvas-as-container-006.html fail

https://bugs.webkit.org/show_bug.cgi?id=253936
rdar://106739131

Reviewed by Alan Baradlay.

When resolving computed style in a non-rendered subtree we fail to take container queries into account.

* LayoutTests/imported/w3c/web-platform-tests/css/css-contain/container-queries/canvas-as-container-005-expected.txt:
* LayoutTests/imported/w3c/web-platform-tests/css/css-contain/container-queries/canvas-as-container-006-expected.txt:
* Source/WebCore/dom/Document.cpp:
(WebCore::Document::styleForElementIgnoringPendingStylesheets):

Take care to have updated document style if it is not clean and we are resolving the root element.

* Source/WebCore/dom/Element.cpp:
(WebCore::Element::resolveComputedStyle):

- Ensure the style scope is flushed so stylesheet data is current.
- Don't bail out when encountering display:none subtree, the ancestors may still affect its style.
- Fall back to a full style update if we encounter a query container with invalid style in the ancestor chain.

Canonical link: https://commits.webkit.org/267786@main

LayoutTests/imported/w3c/web-platform-tests/css/css-contain/container-queries/canvas-as-container-005-expected.txt

@@ -1,6 +1,6 @@
 Test passes if there is a filled green square.
 
 
-FAIL Initially display:none, not focusable assert_not_equals: got disallowed value Element node <div id="target" tabindex="1"></div>
+PASS Initially display:none, not focusable
 PASS Focusable after container size change
 

LayoutTests/imported/w3c/web-platform-tests/css/css-contain/container-queries/canvas-as-container-006-expected.txt

@@ -1,6 +1,6 @@
 Test passes if there is a filled green square.
 
 
-FAIL Initially display:none, not focusable assert_not_equals: got disallowed value Element node <div id="target" tabindex="1"></div>
+PASS Initially display:none, not focusable
 PASS Focusable after container size change
 

Source/WebCore/dom/Document.cpp

@@ -2339,6 +2339,12 @@ std::unique_ptr<RenderStyle> Document::styleForElementIgnoringPendingStylesheets
     ASSERT(pseudoElementSpecifier == PseudoId::None || parentStyle);
     ASSERT(Style::postResolutionCallbacksAreSuspended());
 
+    std::optional<RenderStyle> updatedDocumentStyle;
+    if (!parentStyle && m_needsFullStyleRebuild) {
+        updatedDocumentStyle.emplace(Style::resolveForDocument(*this));
+        parentStyle = &*updatedDocumentStyle;
+    }
+
     SetForScope change(m_ignorePendingStylesheets, true);
     auto& resolver = element.styleResolver();
 

Source/WebCore/dom/Element.cpp

@@ -3965,6 +3965,8 @@ const RenderStyle* Element::resolveComputedStyle(ResolveComputedStyleMode mode)
 {
     ASSERT(isConnected());
 
+    document().styleScope().flushPendingUpdate();
+
     bool isInDisplayNoneTree = false;
 
     // Traverse the ancestor chain to find the rootmost element that has invalid computed style.
@@ -3993,17 +3995,18 @@ const RenderStyle* Element::resolveComputedStyle(ResolveComputedStyleMode mode)
             }
             if (mode == ResolveComputedStyleMode::RenderedOnly && existing->display() == DisplayType::None) {
                 isInDisplayNoneTree = true;
-                return nullptr;
+                // Invalid ancestor style may still affect this display:none style.
+                rootmost = nullptr;
             }
         }
         return rootmost;
     }();
 
-    if (isInDisplayNoneTree)
-        return nullptr;
-
-    if (!rootmostInvalidElement)
+    if (!rootmostInvalidElement) {
+        if (isInDisplayNoneTree)
+            return nullptr;
         return existingComputedStyle();
+    }
 
     auto* ancestorWithValidStyle = rootmostInvalidElement->parentElementInComposedTree();
 
@@ -4020,6 +4023,11 @@ const RenderStyle* Element::resolveComputedStyle(ResolveComputedStyleMode mode)
     // FIXME: This is not as efficient as it could be. For example if an ancestor has a non-inherited style change but
     // the styles are otherwise clean we would not need to re-resolve descendants.
     for (auto& element : makeReversedRange(elementsRequiringComputedStyle)) {
+        if (computedStyle && computedStyle->containerType() != ContainerType::Normal) {
+            // If we find a query container we need to bail out and do full style update to resolve it.
+            if (document().updateStyleIfNeeded())
+                return this->computedStyle();
+        };
         auto style = document().styleForElementIgnoringPendingStylesheets(*element, computedStyle);
         computedStyle = style.get();
         ElementRareData& rareData = element->ensureElementRareData();