Auto merge of #17429 - emilio:restyle-hints-xbl, r=heycam

style: Get restyle hints right in presence of XBL.

Fixes bug 1371130.

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components/style/dom.rs

@@ -332,6 +332,23 @@ pub trait TElement : Eq + PartialEq + Debug + Hash + Sized + Copy + Clone +
         self.parent_element()
     }
 
+    /// The ::before pseudo-element of this element, if it exists.
+    fn before_pseudo_element(&self) -> Option<Self> {
+        None
+    }
+
+    /// The ::after pseudo-element of this element, if it exists.
+    fn after_pseudo_element(&self) -> Option<Self> {
+        None
+    }
+
+    /// Execute `f` for each anonymous content child (apart from ::before and
+    /// ::after) whose originating element is `self`.
+    fn each_anonymous_content_child<F>(&self, _f: F)
+    where
+        F: FnMut(Self),
+    {}
+
     /// For a given NAC element, return the closest non-NAC ancestor, which is
     /// guaranteed to exist.
     fn closest_non_native_anonymous_ancestor(&self) -> Option<Self> {
@@ -570,6 +587,14 @@ pub trait TElement : Eq + PartialEq + Debug + Hash + Sized + Copy + Clone +
         return data.restyle.hint.has_animation_hint()
     }
 
+    /// Returns the anonymous content for the current element's XBL binding,
+    /// given if any.
+    ///
+    /// This is used in Gecko for XBL and shadow DOM.
+    fn xbl_binding_anonymous_content(&self) -> Option<Self::ConcreteNode> {
+        None
+    }
+
     /// Gets declarations from XBL bindings from the element. Only gecko element could have this.
     fn get_declarations_from_xbl_bindings<V>(&self,
                                              _pseudo_element: Option<&PseudoElement>,

components/style/gecko/generated/bindings.rs

@@ -10,6 +10,7 @@ use gecko_bindings::structs::mozilla::css::ImageValue;
 use gecko_bindings::structs::mozilla::css::URLValue;
 use gecko_bindings::structs::mozilla::MallocSizeOf;
 use gecko_bindings::structs::mozilla::Side;
+use gecko_bindings::structs::nsIContent;
 use gecko_bindings::structs::RawGeckoAnimationPropertySegment;
 use gecko_bindings::structs::RawGeckoComputedTiming;
 use gecko_bindings::structs::RawGeckoCSSPropertyIDList;
@@ -506,45 +507,38 @@ extern "C" {
                                     text_is_significant: bool,
                                     whitespace_is_significant: bool) -> bool;
 }
-extern "C" {
-    pub fn Gecko_GetFlattenedTreeParentNode(node: RawGeckoNodeBorrowed)
-     -> RawGeckoNodeBorrowedOrNull;
-}
-extern "C" {
-    pub fn Gecko_GetFirstChild(node: RawGeckoNodeBorrowed)
-     -> RawGeckoNodeBorrowedOrNull;
-}
 extern "C" {
     pub fn Gecko_GetLastChild(node: RawGeckoNodeBorrowed)
      -> RawGeckoNodeBorrowedOrNull;
 }
 extern "C" {
-    pub fn Gecko_GetPrevSibling(node: RawGeckoNodeBorrowed)
+    pub fn Gecko_GetFlattenedTreeParentNode(node: RawGeckoNodeBorrowed)
      -> RawGeckoNodeBorrowedOrNull;
 }
 extern "C" {
-    pub fn Gecko_GetNextSibling(node: RawGeckoNodeBorrowed)
-     -> RawGeckoNodeBorrowedOrNull;
+    pub fn Gecko_GetBeforeOrAfterPseudo(element: RawGeckoElementBorrowed,
+                                        is_before: bool)
+     -> RawGeckoElementBorrowedOrNull;
 }
 extern "C" {
-    pub fn Gecko_GetFirstChildElement(element: RawGeckoElementBorrowed)
-     -> RawGeckoElementBorrowedOrNull;
+    pub fn Gecko_GetAnonymousContentForElement(element:
+                                                   RawGeckoElementBorrowed)
+     -> *mut nsTArray<*mut nsIContent>;
 }
 extern "C" {
-    pub fn Gecko_GetLastChildElement(element: RawGeckoElementBorrowed)
-     -> RawGeckoElementBorrowedOrNull;
+    pub fn Gecko_DestroyAnonymousContentList(anon_content:
+                                                 *mut nsTArray<*mut nsIContent>);
 }
 extern "C" {
-    pub fn Gecko_GetPrevSiblingElement(element: RawGeckoElementBorrowed)
-     -> RawGeckoElementBorrowedOrNull;
+    pub fn Gecko_MaybeCreateStyleChildrenIterator(node: RawGeckoNodeBorrowed)
+     -> StyleChildrenIteratorOwnedOrNull;
 }
 extern "C" {
-    pub fn Gecko_GetNextSiblingElement(element: RawGeckoElementBorrowed)
-     -> RawGeckoElementBorrowedOrNull;
+    pub fn Gecko_DropStyleChildrenIterator(it: StyleChildrenIteratorOwned);
 }
 extern "C" {
-    pub fn Gecko_GetDocumentElement(document: RawGeckoDocumentBorrowed)
-     -> RawGeckoElementBorrowedOrNull;
+    pub fn Gecko_GetNextStyleChild(it: StyleChildrenIteratorBorrowedMut)
+     -> RawGeckoNodeBorrowedOrNull;
 }
 extern "C" {
     pub fn Gecko_LoadStyleSheet(loader: *mut Loader,
@@ -556,22 +550,6 @@ extern "C" {
                                 url_bytes: *const u8, url_length: u32,
                                 media_list: RawServoMediaListStrong);
 }
-extern "C" {
-    pub fn Gecko_MaybeCreateStyleChildrenIterator(node: RawGeckoNodeBorrowed)
-     -> StyleChildrenIteratorOwnedOrNull;
-}
-extern "C" {
-    pub fn Gecko_DropStyleChildrenIterator(it: StyleChildrenIteratorOwned);
-}
-extern "C" {
-    pub fn Gecko_GetNextStyleChild(it: StyleChildrenIteratorBorrowedMut)
-     -> RawGeckoNodeBorrowedOrNull;
-}
-extern "C" {
-    pub fn Gecko_ElementHasBindingWithAnonymousContent(element:
-                                                           RawGeckoElementBorrowed)
-     -> bool;
-}
 extern "C" {
     pub fn Gecko_ElementState(element: RawGeckoElementBorrowed) -> u64;
 }
@@ -1041,6 +1019,11 @@ extern "C" {
                                                       *mut nsStyleGridTemplate,
                                                   track_sizes: u32);
 }
+extern "C" {
+    pub fn Gecko_SetGridTemplateLineNamesLength(grid_template:
+                                                    *mut nsStyleGridTemplate,
+                                                track_sizes: u32);
+}
 extern "C" {
     pub fn Gecko_CopyStyleGridTemplateValues(grid_template:
                                                  *mut nsStyleGridTemplate,
@@ -1942,6 +1925,17 @@ extern "C" {
                                                      RawServoDeclarationBlockBorrowed)
      -> ServoComputedValuesStrong;
 }
+extern "C" {
+    pub fn Servo_StyleSet_MightHaveAttributeDependency(set:
+                                                           RawServoStyleSetBorrowed,
+                                                       local_name:
+                                                           *mut nsIAtom)
+     -> bool;
+}
+extern "C" {
+    pub fn Servo_StyleSet_HasStateDependency(set: RawServoStyleSetBorrowed,
+                                             state: u64) -> bool;
+}
 extern "C" {
     pub fn Servo_CssRules_ListTypes(rules: ServoCssRulesBorrowed,
                                     result: nsTArrayBorrowed_uintptr_t);
@@ -2683,6 +2677,9 @@ extern "C" {
 extern "C" {
     pub fn Servo_AssertTreeIsClean(root: RawGeckoElementBorrowed);
 }
+extern "C" {
+    pub fn Servo_MaybeGCRuleTree(set: RawServoStyleSetBorrowed);
+}
 extern "C" {
     pub fn Servo_StyleSet_GetBaseComputedValuesForElement(set:
                                                               RawServoStyleSetBorrowed,