Auto merge of #5753 - JIoJIaJIu:timeline, r=jdm

RequestAnimationFrame
[Task](https://github.com/servo/servo/issues/5681)

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components/script/dom/bindings/trace.rs

@@ -281,6 +281,13 @@ impl JSTraceable for Box<ScriptChan+Send> {
     }
 }
 
+impl JSTraceable for Box<Fn(f64, )> {
+    #[inline]
+    fn trace(&self, _trc: *mut JSTracer) {
+        // Do nothing
+    }
+}
+
 impl<'a> JSTraceable for &'a str {
     #[inline]
     fn trace(&self, _: *mut JSTracer) {

components/script/dom/document.rs

@@ -11,6 +11,8 @@ use dom::bindings::codegen::Bindings::EventHandlerBinding::EventHandlerNonNull;
 use dom::bindings::codegen::Bindings::EventTargetBinding::EventTargetMethods;
 use dom::bindings::codegen::Bindings::NodeBinding::NodeMethods;
 use dom::bindings::codegen::Bindings::NodeFilterBinding::NodeFilter;
+use dom::bindings::codegen::Bindings::PerformanceBinding::PerformanceMethods;
+use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
 use dom::bindings::codegen::InheritTypes::{DocumentDerived, EventCast, HTMLBodyElementCast};
 use dom::bindings::codegen::InheritTypes::{HTMLElementCast, HTMLHeadElementCast, ElementCast};
 use dom::bindings::codegen::InheritTypes::{DocumentTypeCast, HTMLHtmlElementCast, NodeCast};
@@ -63,6 +65,7 @@ use dom::window::{Window, WindowHelpers, ReflowReason};
 
 use layout_interface::{HitTestResponse, MouseOverResponse};
 use msg::compositor_msg::ScriptListener;
+use msg::constellation_msg::AnimationState;
 use msg::constellation_msg::Msg as ConstellationMsg;
 use msg::constellation_msg::{ConstellationChan, FocusType, Key, KeyState, KeyModifiers, MozBrowserEvent};
 use msg::constellation_msg::{SUPER, ALT, SHIFT, CONTROL};
@@ -82,11 +85,12 @@ use url::Url;
 use js::jsapi::JSRuntime;
 
 use num::ToPrimitive;
+use std::iter::FromIterator;
 use std::borrow::ToOwned;
 use std::collections::HashMap;
 use std::collections::hash_map::Entry::{Occupied, Vacant};
 use std::ascii::AsciiExt;
-use std::cell::{Cell, Ref};
+use std::cell::{Cell, Ref, RefCell};
 use std::default::Default;
 use std::sync::mpsc::channel;
 use time;
@@ -129,6 +133,12 @@ pub struct Document {
     /// https://html.spec.whatwg.org/multipage/#concept-n-noscript
     /// True if scripting is enabled for all scripts in this document
     scripting_enabled: Cell<bool>,
+    /// https://html.spec.whatwg.org/multipage/#animation-frame-callback-identifier
+    /// Current identifier of animation frame callback
+    animation_frame_ident: Cell<i32>,
+    /// https://html.spec.whatwg.org/multipage/#list-of-animation-frame-callbacks
+    /// List of animation frame callbacks
+    animation_frame_list: RefCell<HashMap<i32, Box<Fn(f64)>>>,
 }
 
 impl DocumentDerived for EventTarget {
@@ -238,6 +248,12 @@ pub trait DocumentHelpers<'a> {
 
     fn set_current_script(self, script: Option<JSRef<HTMLScriptElement>>);
     fn trigger_mozbrowser_event(self, event: MozBrowserEvent);
+    /// http://w3c.github.io/animation-timing/#dom-windowanimationtiming-requestanimationframe
+    fn request_animation_frame(self, callback: Box<Fn(f64, )>) -> i32;
+    /// http://w3c.github.io/animation-timing/#dom-windowanimationtiming-cancelanimationframe
+    fn cancel_animation_frame(self, ident: i32);
+    /// http://w3c.github.io/animation-timing/#dfn-invoke-callbacks-algorithm
+    fn invoke_animation_callbacks(self);
 }
 
 impl<'a> DocumentHelpers<'a> for JSRef<'a, Document> {
@@ -793,6 +809,61 @@ impl<'a> DocumentHelpers<'a> for JSRef<'a, Document> {
             }
         }
     }
+
+    /// http://w3c.github.io/animation-timing/#dom-windowanimationtiming-requestanimationframe
+    fn request_animation_frame(self, callback: Box<Fn(f64, )>) -> i32 {
+        let window = self.window.root();
+        let window = window.r();
+        let ident = self.animation_frame_ident.get() + 1;
+
+        self.animation_frame_ident.set(ident);
+        self.animation_frame_list.borrow_mut().insert(ident, callback);
+
+        // TODO: Should tick animation only when document is visible
+        let ConstellationChan(ref chan) = window.constellation_chan();
+        let event = ConstellationMsg::ChangeRunningAnimationsState(window.pipeline(),
+                                                                   AnimationState::AnimationCallbacksPresent);
+        chan.send(event).unwrap();
+
+        ident
+    }
+
+    /// http://w3c.github.io/animation-timing/#dom-windowanimationtiming-cancelanimationframe
+    fn cancel_animation_frame(self, ident: i32) {
+        self.animation_frame_list.borrow_mut().remove(&ident);
+        if self.animation_frame_list.borrow().len() == 0 {
+            let window = self.window.root();
+            let window = window.r();
+            let ConstellationChan(ref chan) = window.constellation_chan();
+            let event = ConstellationMsg::ChangeRunningAnimationsState(window.pipeline(),
+                                                                       AnimationState::NoAnimationCallbacksPresent);
+            chan.send(event).unwrap();
+        }
+    }
+
+    /// http://w3c.github.io/animation-timing/#dfn-invoke-callbacks-algorithm
+    fn invoke_animation_callbacks(self) {
+        let animation_frame_list;
+        {
+            let mut list = self.animation_frame_list.borrow_mut();
+            animation_frame_list = Vec::from_iter(list.drain());
+
+            let window = self.window.root();
+            let window = window.r();
+            let ConstellationChan(ref chan) = window.constellation_chan();
+            let event = ConstellationMsg::ChangeRunningAnimationsState(window.pipeline(),
+                                                                       AnimationState::NoAnimationCallbacksPresent);
+            chan.send(event).unwrap();
+        }
+        let window = self.window.root();
+        let window = window.r();
+        let performance = window.Performance().root();
+        let performance = performance.r();
+
+        for (_, callback) in animation_frame_list {
+            callback(*performance.Now());
+        }
+    }
 }
 
 pub enum MouseEventType {
@@ -870,6 +941,8 @@ impl Document {
             focused: Default::default(),
             current_script: Default::default(),
             scripting_enabled: Cell::new(true),
+            animation_frame_ident: Cell::new(0),
+            animation_frame_list: RefCell::new(HashMap::new()),
         }
     }
 

components/script/dom/webidls/Window.webidl

@@ -141,3 +141,10 @@ interface WindowLocalStorage {
   readonly attribute Storage localStorage;
 };
 Window implements WindowLocalStorage;
+
+// http://w3c.github.io/animation-timing/#Window-interface-extensions
+partial interface Window {
+  long requestAnimationFrame(FrameRequestCallback callback);
+  void cancelAnimationFrame(long handle);
+};
+callback FrameRequestCallback = void (DOMHighResTimeStamp time);

components/script/dom/window.rs

@@ -3,11 +3,11 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use dom::bindings::cell::DOMRefCell;
+use dom::bindings::callback::ExceptionHandling;
 use dom::bindings::codegen::Bindings::EventHandlerBinding::{OnErrorEventHandlerNonNull, EventHandlerNonNull};
-use dom::bindings::codegen::Bindings::FunctionBinding::Function;
-use dom::bindings::codegen::Bindings::WindowBinding;
-use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
 use dom::bindings::codegen::Bindings::DocumentBinding::DocumentMethods;
+use dom::bindings::codegen::Bindings::FunctionBinding::Function;
+use dom::bindings::codegen::Bindings::WindowBinding::{self, WindowMethods, FrameRequestCallback};
 use dom::bindings::codegen::InheritTypes::{NodeCast, EventTargetCast};
 use dom::bindings::global::global_object_for_js_object;
 use dom::bindings::error::{report_pending_exception, Fallible};
@@ -15,6 +15,7 @@ use dom::bindings::error::Error::InvalidCharacter;
 use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JS, JSRef, MutNullableHeap, OptionalRootable};
 use dom::bindings::js::{Rootable, RootedReference, Temporary};
+use dom::bindings::num::Finite;
 use dom::bindings::utils::{GlobalStaticData, Reflectable, WindowProxyHandler};
 use dom::browsercontext::BrowserContext;
 use dom::console::Console;
@@ -464,6 +465,24 @@ impl<'a> WindowMethods for JSRef<'a, Window> {
     fn Atob(self, atob: DOMString) -> Fallible<DOMString> {
         base64_atob(atob)
     }
+
+    /// http://w3c.github.io/animation-timing/#dom-windowanimationtiming-requestanimationframe
+    fn RequestAnimationFrame(self, callback: FrameRequestCallback) -> i32 {
+        let doc = self.Document().root();
+
+        let callback  = move |now: f64| {
+            // TODO: @jdm The spec says that any exceptions should be suppressed;
+            callback.Call__(Finite::wrap(now), ExceptionHandling::Report).unwrap();
+        };
+
+        doc.r().request_animation_frame(Box::new(callback))
+    }
+
+    /// http://w3c.github.io/animation-timing/#dom-windowanimationtiming-cancelanimationframe
+    fn CancelAnimationFrame(self, ident: i32) {
+        let doc = self.Document().root();
+        doc.r().cancel_animation_frame(ident);
+    }
 }
 
 pub trait WindowHelpers {