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

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

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1 files changed, 7 insertions, 1 deletions

diff --git a/components/script/devtools.rs b/components/script/devtools.rs
index cdc0537fa15..d67f57b4e4f 100644
--- a/components/script/devtools.rs
+++ b/components/script/devtools.rs
@@ -14,7 +14,7 @@ use dom::node::{Node, NodeHelpers};
 use dom::window::{WindowHelpers, ScriptHelpers};
 use dom::element::Element;
 use dom::document::DocumentHelpers;
-use page::Page;
+use page::{IterablePage, Page};
 use msg::constellation_msg::PipelineId;
 use script_task::{get_page, ScriptTask};
 
@@ -147,3 +147,9 @@ pub fn handle_drop_timeline_markers(page: &Rc<Page>,
         }
     }
 }
+
+pub fn handle_request_animation_frame(page: &Rc<Page>, id: PipelineId, callback: Box<Fn(f64, )>) {
+    let page = page.find(id).expect("There is no such page");
+    let doc = page.document().root();
+    doc.r().request_animation_frame(callback);
+}