Introduce UpdateAnimationTasks to perform a bunch of animation's tasks in a SequentialTask.

The UpdateAnimationsTasks is a bitflags and each bit is generated from
Gecko's UpdateAnimationsTasks (enum class) values for matching values
between C++ and Rust. For this reason, the bitflags is annotated as
(feature = "gecko"), as a result update_animations() which uses this bitflags
also became gecko-only function.

components/script/layout_wrapper.rs

@@ -451,10 +451,6 @@ impl<'le> TElement for ServoLayoutElement<'le> {
         self.element.has_selector_flags(flags)
     }
 
-    fn update_animations(&self, _pseudo: Option<&PseudoElement>) {
-        panic!("this should be only called on gecko");
-    }
-
     fn has_animations(&self, _pseudo: Option<&PseudoElement>) -> bool {
         panic!("this should be only called on gecko");
     }

components/style/build_gecko.rs

@@ -282,7 +282,8 @@ mod bindings {
             .raw_line("use data::ElementData;")
             .hide_type("nsString")
             .bitfield_enum("nsChangeHint")
-            .bitfield_enum("nsRestyleHint");
+            .bitfield_enum("nsRestyleHint")
+            .constified_enum("UpdateAnimationsTasks");
         let whitelist_vars = [
             "NS_THEME_.*",
             "NODE_.*",
@@ -306,6 +307,7 @@ mod bindings {
             "mozilla::TraversalRootBehavior",
             "mozilla::StyleShapeRadius",
             "mozilla::StyleGrid.*",
+            "mozilla::UpdateAnimationsTasks",
             "mozilla::LookAndFeel",
             ".*ThreadSafe.*Holder",
             "AnonymousContent",
@@ -667,6 +669,7 @@ mod bindings {
             "Loader",
             "ServoStyleSheet",
             "EffectCompositor_CascadeLevel",
+            "UpdateAnimationsTasks",
         ];
         struct ArrayType {
             cpp_type: &'static str,

components/style/context.rs

@@ -12,9 +12,10 @@ use data::ElementData;
 use dom::{OpaqueNode, TNode, TElement, SendElement};
 use error_reporting::ParseErrorReporter;
 use euclid::Size2D;
+#[cfg(feature = "gecko")] use gecko_bindings::structs;
 use matching::StyleSharingCandidateCache;
 use parking_lot::RwLock;
-use selector_parser::PseudoElement;
+#[cfg(feature = "gecko")] use selector_parser::PseudoElement;
 use selectors::matching::ElementSelectorFlags;
 use servo_config::opts;
 use shared_lock::StylesheetGuards;
@@ -194,6 +195,22 @@ impl TraversalStatistics {
     }
 }
 
+#[cfg(feature = "gecko")]
+bitflags! {
+    /// Represents which tasks are performed in a SequentialTask of UpdateAnimations.
+    pub flags UpdateAnimationsTasks: u8 {
+        /// Update CSS Animations.
+        const CSS_ANIMATIONS = structs::UpdateAnimationsTasks_CSSAnimations,
+        /// Update CSS Transitions.
+        const CSS_TRANSITIONS = structs::UpdateAnimationsTasks_CSSTransitions,
+        /// Update effect properties.
+        const EFFECT_PROPERTIES = structs::UpdateAnimationsTasks_EffectProperties,
+        /// Update animation cacade results for animations running on the compositor.
+        const CASCADE_RESULTS = structs::UpdateAnimationsTasks_CascadeResults,
+    }
+}
+
+
 /// A task to be run in sequential mode on the parent (non-worker) thread. This
 /// is used by the style system to queue up work which is not safe to do during
 /// the parallel traversal.
@@ -202,9 +219,10 @@ pub enum SequentialTask<E: TElement> {
     /// element that we don't have exclusive access to (i.e. the parent).
     SetSelectorFlags(SendElement<E>, ElementSelectorFlags),
 
-    /// Marks that we need to create/remove/update CSS animations after the
+    #[cfg(feature = "gecko")]
-    /// first traversal.
+    /// Marks that we need to update CSS animations, update effect properties of
-    UpdateAnimations(SendElement<E>, Option<PseudoElement>),
+    /// any type of animations after the normal traversal.
+    UpdateAnimations(SendElement<E>, Option<PseudoElement>, UpdateAnimationsTasks),
 }
 
 impl<E: TElement> SequentialTask<E> {
@@ -216,8 +234,9 @@ impl<E: TElement> SequentialTask<E> {
             SetSelectorFlags(el, flags) => {
                 unsafe { el.set_selector_flags(flags) };
             }
-            UpdateAnimations(el, pseudo) => {
+            #[cfg(feature = "gecko")]
-                unsafe { el.update_animations(pseudo.as_ref()) };
+            UpdateAnimations(el, pseudo, tasks) => {
+                unsafe { el.update_animations(pseudo.as_ref(), tasks) };
             }
         }
     }
@@ -228,10 +247,12 @@ impl<E: TElement> SequentialTask<E> {
         SetSelectorFlags(unsafe { SendElement::new(el) }, flags)
     }
 
-    /// Creates a task to update CSS Animations on a given (pseudo-)element.
+    #[cfg(feature = "gecko")]
-    pub fn update_animations(el: E, pseudo: Option<PseudoElement>) -> Self {
+    /// Creates a task to update various animation state on a given (pseudo-)element.
+    pub fn update_animations(el: E, pseudo: Option<PseudoElement>,
+                             tasks: UpdateAnimationsTasks) -> Self {
         use self::SequentialTask::*;
-        UpdateAnimations(unsafe { SendElement::new(el) }, pseudo)
+        UpdateAnimations(unsafe { SendElement::new(el) }, pseudo, tasks)
     }
 }
 

components/style/dom.rs

@@ -9,6 +9,7 @@
 
 use {Atom, Namespace, LocalName};
 use atomic_refcell::{AtomicRef, AtomicRefCell, AtomicRefMut};
+#[cfg(feature = "gecko")] use context::UpdateAnimationsTasks;
 use data::ElementData;
 use element_state::ElementState;
 use properties::{ComputedValues, PropertyDeclarationBlock};
@@ -366,9 +367,10 @@ pub trait TElement : PartialEq + Debug + Sized + Copy + Clone + ElementExt + Pre
     /// Returns true if the element has all the specified selector flags.
     fn has_selector_flags(&self, flags: ElementSelectorFlags) -> bool;
 
-    /// Creates a task to update CSS Animations on a given (pseudo-)element.
+    /// Creates a task to update various animation state on a given (pseudo-)element.
-    /// Note: Gecko only.
+    #[cfg(feature = "gecko")]
-    fn update_animations(&self, _pseudo: Option<&PseudoElement>);
+    fn update_animations(&self, _pseudo: Option<&PseudoElement>,
+                         tasks: UpdateAnimationsTasks);
 
     /// Returns true if the element has relevant animations. Relevant
     /// animations are those animations that are affecting the element's style

components/style/gecko/wrapper.rs

@@ -15,6 +15,7 @@
 //! the separation between the style system implementation and everything else.
 
 use atomic_refcell::AtomicRefCell;
+use context::UpdateAnimationsTasks;
 use data::ElementData;
 use dom::{AnimationRules, LayoutIterator, NodeInfo, TElement, TNode, UnsafeNode};
 use dom::{OpaqueNode, PresentationalHintsSynthetizer};
@@ -555,7 +556,8 @@ impl<'le> TElement for GeckoElement<'le> {
         (self.flags() & node_flags) == node_flags
     }
 
-    fn update_animations(&self, pseudo: Option<&PseudoElement>) {
+    fn update_animations(&self, pseudo: Option<&PseudoElement>,
+                         tasks: UpdateAnimationsTasks) {
         // We have to update animations even if the element has no computed style
         // since it means the element is in a display:none subtree, we should destroy
         // all CSS animations in display:none subtree.
@@ -584,7 +586,8 @@ impl<'le> TElement for GeckoElement<'le> {
         unsafe {
             Gecko_UpdateAnimations(self.0, atom_ptr,
                                    computed_values_opt,
-                                   parent_values_opt);
+                                   parent_values_opt,
+                                   tasks.bits());
         }
     }
 

components/style/gecko_bindings/bindings.rs

@@ -176,6 +176,7 @@ use gecko_bindings::structs::nsresult;
 use gecko_bindings::structs::Loader;
 use gecko_bindings::structs::ServoStyleSheet;
 use gecko_bindings::structs::EffectCompositor_CascadeLevel;
+use gecko_bindings::structs::UpdateAnimationsTasks;
 pub type nsTArrayBorrowed_uintptr_t<'a> = &'a mut ::gecko_bindings::structs::nsTArray<usize>;
 pub type ServoCssRulesStrong = ::gecko_bindings::sugar::ownership::Strong<ServoCssRules>;
 pub type ServoCssRulesBorrowed<'a> = &'a ServoCssRules;
@@ -610,7 +611,8 @@ extern "C" {
                                   aComputedValues:
                                       ServoComputedValuesBorrowedOrNull,
                                   aParentComputedValues:
-                                      ServoComputedValuesBorrowedOrNull);
+                                      ServoComputedValuesBorrowedOrNull,
+                                  aTaskBits: UpdateAnimationsTasks);
 }
 extern "C" {
     pub fn Gecko_ElementHasAnimations(aElement: RawGeckoElementBorrowed,

components/style/gecko_bindings/structs_debug.rs

@@ -6151,6 +6151,19 @@ pub mod root {
             Normal = 0,
             UnstyledChildrenOnly = 1,
         }
+        pub const UpdateAnimationsTasks_CSSAnimations:
+                  root::mozilla::UpdateAnimationsTasks =
+            1;
+        pub const UpdateAnimationsTasks_CSSTransitions:
+                  root::mozilla::UpdateAnimationsTasks =
+            2;
+        pub const UpdateAnimationsTasks_EffectProperties:
+                  root::mozilla::UpdateAnimationsTasks =
+            4;
+        pub const UpdateAnimationsTasks_CascadeResults:
+                  root::mozilla::UpdateAnimationsTasks =
+            8;
+        pub type UpdateAnimationsTasks = u8;
         pub type CSSPseudoElementTypeBase = u8;
         pub const CSSPseudoElementType_InheritingAnonBox:
                   root::mozilla::CSSPseudoElementType =

components/style/gecko_bindings/structs_release.rs

@@ -6066,6 +6066,19 @@ pub mod root {
             Normal = 0,
             UnstyledChildrenOnly = 1,
         }
+        pub const UpdateAnimationsTasks_CSSAnimations:
+                  root::mozilla::UpdateAnimationsTasks =
+            1;
+        pub const UpdateAnimationsTasks_CSSTransitions:
+                  root::mozilla::UpdateAnimationsTasks =
+            2;
+        pub const UpdateAnimationsTasks_EffectProperties:
+                  root::mozilla::UpdateAnimationsTasks =
+            4;
+        pub const UpdateAnimationsTasks_CascadeResults:
+                  root::mozilla::UpdateAnimationsTasks =
+            8;
+        pub type UpdateAnimationsTasks = u8;
         pub type CSSPseudoElementTypeBase = u8;
         pub const CSSPseudoElementType_InheritingAnonBox:
                   root::mozilla::CSSPseudoElementType =

components/style/matching.rs

@@ -638,11 +638,15 @@ trait PrivateMatchMethods: TElement {
                           new_values: &mut Arc<ComputedValues>,
                           pseudo: Option<&PseudoElement>,
                           _possibly_expired_animations: &mut Vec<PropertyAnimation>) {
+        use context::CSS_ANIMATIONS;
+        use context::UpdateAnimationsTasks;
+
         let ref new_box_style = new_values.get_box();
         let has_new_animation_style = new_box_style.animation_name_count() >= 1 &&
                                       new_box_style.animation_name_at(0).0.len() != 0;
         let has_animations = self.has_css_animations(pseudo);
 
+        let mut tasks = UpdateAnimationsTasks::empty();
         let needs_update_animations =
             old_values.as_ref().map_or(has_new_animation_style, |ref old| {
                 let ref old_box_style = old.get_box();
@@ -658,8 +662,12 @@ trait PrivateMatchMethods: TElement {
                   has_animations)
             });
         if needs_update_animations {
+            tasks.insert(CSS_ANIMATIONS);
+        }
+        if !tasks.is_empty() {
             let task = SequentialTask::update_animations(self.as_node().as_element().unwrap(),
-                                                         pseudo.cloned());
+                                                         pseudo.cloned(),
+                                                         tasks);
             context.thread_local.tasks.push(task);
         }
     }