LibWeb: Implement generic boolean logic for media/supports queries

CSS Values 5 now defines a `<boolean-expr[]>` type that is used in place
of the bespoke grammar that previously existed for `@media` and
`@supports` queries. This commit implements some BooleanExpression
types to represent the nodes in a `<boolean-expr[]>`, and reimplements
`@media` and `@supports` queries using this.

The one part of this implementation I'm not convinced on is that the
`evaluate()` methods take a `HTML::Window*`. This is a compromise
because `@media` requires a Window, and `@supports` does not require
anything at all. As more users of `<boolean-expr[]>` get implemented in
the future, it will become clear if this is sufficient, or if we need
to do something smarter.

As a bonus, this actually improves our serialization of media queries!

Libraries/LibWeb/CSS/BooleanExpression.cpp

@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 2021-2025, Sam Atkins <sam@ladybird.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/StringBuilder.h>
+#include <LibWeb/CSS/BooleanExpression.h>
+
+namespace Web::CSS {
+
+bool BooleanExpression::evaluate_to_boolean(HTML::Window const* window) const
+{
+    return evaluate(window) == MatchResult::True;
+}
+
+void BooleanExpression::indent(StringBuilder& builder, int levels)
+{
+    builder.append_repeated("  "sv, levels);
+}
+
+void GeneralEnclosed::dump(StringBuilder& builder, int indent_levels) const
+{
+    indent(builder, indent_levels);
+    builder.appendff("GeneralEnclosed: {}\n", to_string());
+}
+
+MatchResult BooleanNotExpression::evaluate(HTML::Window const* window) const
+{
+    // https://drafts.csswg.org/css-values-5/#boolean-logic
+    // `not test` evaluates to true if its contained test is false, false if it’s true, and unknown if it’s unknown.
+    switch (m_child->evaluate(window)) {
+    case MatchResult::False:
+        return MatchResult::True;
+    case MatchResult::True:
+        return MatchResult::False;
+    case MatchResult::Unknown:
+        return MatchResult::Unknown;
+    }
+    VERIFY_NOT_REACHED();
+}
+
+String BooleanNotExpression::to_string() const
+{
+    return MUST(String::formatted("not {}", m_child->to_string()));
+}
+
+void BooleanNotExpression::dump(StringBuilder& builder, int indent_levels) const
+{
+    indent(builder, indent_levels);
+    builder.append("NOT:\n"sv);
+    m_child->dump(builder, indent_levels + 1);
+}
+
+MatchResult BooleanExpressionInParens::evaluate(HTML::Window const* window) const
+{
+    return m_child->evaluate(window);
+}
+
+String BooleanExpressionInParens::to_string() const
+{
+    return MUST(String::formatted("({})", m_child->to_string()));
+}
+
+void BooleanExpressionInParens::dump(StringBuilder& builder, int indent_levels) const
+{
+    indent(builder, indent_levels);
+    builder.append("(\n"sv);
+    m_child->dump(builder, indent_levels + 1);
+    indent(builder, indent_levels);
+    builder.append(")\n"sv);
+}
+
+MatchResult BooleanAndExpression::evaluate(HTML::Window const* window) const
+{
+    // https://drafts.csswg.org/css-values-5/#boolean-logic
+    // Multiple tests connected with `and` evaluate to true if all of those tests are true, false if any of them are
+    // false, and unknown otherwise (i.e. if at least one unknown, but no false).
+    size_t true_results = 0;
+    for (auto const& child : m_children) {
+        auto child_match = child->evaluate(window);
+        if (child_match == MatchResult::False)
+            return MatchResult::False;
+        if (child_match == MatchResult::True)
+            true_results++;
+    }
+    if (true_results == m_children.size())
+        return MatchResult::True;
+    return MatchResult::Unknown;
+}
+
+String BooleanAndExpression::to_string() const
+{
+    return MUST(String::join(" and "sv, m_children));
+}
+
+void BooleanAndExpression::dump(StringBuilder& builder, int indent_levels) const
+{
+    indent(builder, indent_levels);
+    builder.append("AND:\n"sv);
+    for (auto const& child : m_children)
+        child->dump(builder, indent_levels + 1);
+}
+
+MatchResult BooleanOrExpression::evaluate(HTML::Window const* window) const
+{
+    // https://drafts.csswg.org/css-values-5/#boolean-logic
+    // Multiple tests connected with `or` evaluate to true if any of those tests are true, false if all of them are
+    // false, and unknown otherwise (i.e. at least one unknown, but no true).
+    size_t false_results = 0;
+    for (auto const& child : m_children) {
+        auto child_match = child->evaluate(window);
+        if (child_match == MatchResult::True)
+            return MatchResult::True;
+        if (child_match == MatchResult::False)
+            false_results++;
+    }
+    if (false_results == m_children.size())
+        return MatchResult::False;
+    return MatchResult::Unknown;
+}
+
+String BooleanOrExpression::to_string() const
+{
+    return MUST(String::join(" or "sv, m_children));
+}
+
+void BooleanOrExpression::dump(StringBuilder& builder, int indent_levels) const
+{
+    indent(builder, indent_levels);
+    builder.append("OR:\n"sv);
+    for (auto const& child : m_children)
+        child->dump(builder, indent_levels + 1);
+}
+
+}