script: Move CSS DOM interfaces to script/dom/css/ (#40241)

Moves interfaces defined by the CSS spec to the `script/dom/css/` module
from `script/dom/`.

Testing: Just a refactor shouldn't need any testing
Fixes: Partially #38901

Signed-off-by: WaterWhisperer <waterwhisperer24@qq.com>

components/script/dom/css/cssgroupingrule.rs

@@ -0,0 +1,107 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use dom_struct::dom_struct;
+use servo_arc::Arc;
+use style::shared_lock::{Locked, SharedRwLock, SharedRwLockReadGuard};
+use style::stylesheets::{CssRuleType, CssRuleTypes, CssRules};
+
+use super::cssconditionrule::CSSConditionRule;
+use super::csslayerblockrule::CSSLayerBlockRule;
+use super::cssrule::CSSRule;
+use super::cssrulelist::{CSSRuleList, RulesSource};
+use super::cssstylerule::CSSStyleRule;
+use super::cssstylesheet::CSSStyleSheet;
+use crate::dom::bindings::codegen::Bindings::CSSGroupingRuleBinding::CSSGroupingRuleMethods;
+use crate::dom::bindings::error::{ErrorResult, Fallible};
+use crate::dom::bindings::inheritance::Castable;
+use crate::dom::bindings::reflector::DomGlobal;
+use crate::dom::bindings::root::{DomRoot, MutNullableDom};
+use crate::dom::bindings::str::DOMString;
+use crate::script_runtime::CanGc;
+
+#[dom_struct]
+pub(crate) struct CSSGroupingRule {
+    cssrule: CSSRule,
+    rulelist: MutNullableDom<CSSRuleList>,
+}
+
+impl CSSGroupingRule {
+    pub(crate) fn new_inherited(parent_stylesheet: &CSSStyleSheet) -> CSSGroupingRule {
+        CSSGroupingRule {
+            cssrule: CSSRule::new_inherited(parent_stylesheet),
+            rulelist: MutNullableDom::new(None),
+        }
+    }
+
+    fn rulelist(&self, can_gc: CanGc) -> DomRoot<CSSRuleList> {
+        let parent_stylesheet = self.upcast::<CSSRule>().parent_stylesheet();
+        self.rulelist.or_init(|| {
+            let rules = if let Some(rule) = self.downcast::<CSSConditionRule>() {
+                rule.clone_rules()
+            } else if let Some(rule) = self.downcast::<CSSLayerBlockRule>() {
+                rule.clone_rules()
+            } else if let Some(rule) = self.downcast::<CSSStyleRule>() {
+                rule.ensure_rules()
+            } else {
+                unreachable!()
+            };
+            CSSRuleList::new(
+                self.global().as_window(),
+                parent_stylesheet,
+                RulesSource::Rules(rules),
+                can_gc,
+            )
+        })
+    }
+
+    pub(crate) fn parent_stylesheet(&self) -> &CSSStyleSheet {
+        self.cssrule.parent_stylesheet()
+    }
+
+    pub(crate) fn shared_lock(&self) -> &SharedRwLock {
+        self.cssrule.shared_lock()
+    }
+
+    pub(crate) fn update_rules(
+        &self,
+        rules: &Arc<Locked<CssRules>>,
+        guard: &SharedRwLockReadGuard,
+    ) {
+        if let Some(rulelist) = self.rulelist.get() {
+            rulelist.update_rules(RulesSource::Rules(rules.clone()), guard);
+        }
+    }
+}
+
+impl CSSGroupingRuleMethods<crate::DomTypeHolder> for CSSGroupingRule {
+    // https://drafts.csswg.org/cssom/#dom-cssgroupingrule-cssrules
+    fn CssRules(&self, can_gc: CanGc) -> DomRoot<CSSRuleList> {
+        // XXXManishearth check origin clean flag
+        self.rulelist(can_gc)
+    }
+
+    // https://drafts.csswg.org/cssom/#dom-cssgroupingrule-insertrule
+    fn InsertRule(&self, rule: DOMString, index: u32, can_gc: CanGc) -> Fallible<u32> {
+        // TODO: this should accumulate the rule types of all ancestors.
+        let rule_type = self.cssrule.as_specific().ty();
+        let containing_rule_types = CssRuleTypes::from(rule_type);
+        let parse_relative_rule_type = match rule_type {
+            CssRuleType::Style | CssRuleType::Scope => Some(rule_type),
+            _ => None,
+        };
+        self.rulelist(can_gc).insert_rule(
+            &rule,
+            index,
+            containing_rule_types,
+            parse_relative_rule_type,
+            can_gc,
+        )
+    }
+
+    // https://drafts.csswg.org/cssom/#dom-cssgroupingrule-deleterule
+    fn DeleteRule(&self, index: u32, can_gc: CanGc) -> ErrorResult {
+        self.rulelist(can_gc).remove_rule(index)
+    }
+}