auto merge of #4956 : psdh/servo/interfail, r=jdm

Fixes #4923

1 files changed, 6 insertions, 5 deletions

diff --git a/components/script/script_task.rs b/components/script/script_task.rs
index f63bd70abbf..f29e5690cf5 100644
--- a/components/script/script_task.rs
+++ b/components/script/script_task.rs
@@ -84,6 +84,7 @@ use std::fmt::{self, Display};
 use std::mem::replace;
 use std::num::ToPrimitive;
 use std::rc::Rc;
+use std::result::Result;
 use std::sync::mpsc::{channel, Sender, Receiver, Select};
 use std::u32;
 use time::{Tm, strptime};
@@ -133,7 +134,7 @@ pub enum ScriptMsg {
 /// A cloneable interface for communicating with an event loop.
 pub trait ScriptChan {
     /// Send a message to the associated event loop.
-    fn send(&self, msg: ScriptMsg);
+    fn send(&self, msg: ScriptMsg) -> Result<(), ()>;
     /// Clone this handle.
     fn clone(&self) -> Box<ScriptChan+Send>;
 }
@@ -143,9 +144,9 @@ pub trait ScriptChan {
 pub struct NonWorkerScriptChan(pub Sender<ScriptMsg>);
 
 impl ScriptChan for NonWorkerScriptChan {
-    fn send(&self, msg: ScriptMsg) {
+    fn send(&self, msg: ScriptMsg) -> Result<(), ()> {
         let NonWorkerScriptChan(ref chan) = *self;
-        chan.send(msg).unwrap();
+        return chan.send(msg).map_err(|_| ());
     }
 
     fn clone(&self) -> Box<ScriptChan+Send> {
@@ -893,7 +894,7 @@ impl ScriptTask {
         // https://html.spec.whatwg.org/multipage/#the-end step 4
         let addr: Trusted<Document> = Trusted::new(self.get_cx(), document.r(), self.chan.clone());
         let handler = Box::new(DocumentProgressHandler::new(addr.clone(), DocumentProgressTask::DOMContentLoaded));
-        self.chan.send(ScriptMsg::RunnableMsg(handler));
+        self.chan.send(ScriptMsg::RunnableMsg(handler)).unwrap();
 
         // We have no concept of a document loader right now, so just dispatch the
         // "load" event as soon as we've finished executing all scripts parsed during
@@ -901,7 +902,7 @@ impl ScriptTask {
 
         // https://html.spec.whatwg.org/multipage/#the-end step 7
         let handler = Box::new(DocumentProgressHandler::new(addr, DocumentProgressTask::Load));
-        self.chan.send(ScriptMsg::RunnableMsg(handler));
+        self.chan.send(ScriptMsg::RunnableMsg(handler)).unwrap();
 
         *page.fragment_name.borrow_mut() = final_url.fragment.clone();