Fixing Intermittent failure in pages with timers

Fixes #4923

8 files changed, 24 insertions, 21 deletions

diff --git a/components/script/dom/bindings/refcounted.rs b/components/script/dom/bindings/refcounted.rs
index a0183aac59c..b7f039cb527 100644
--- a/components/script/dom/bindings/refcounted.rs
+++ b/components/script/dom/bindings/refcounted.rs
@@ -114,7 +114,7 @@ impl<T: Reflectable> Drop for Trusted<T> {
         *refcount -= 1;
         if *refcount == 0 {
             self.script_chan.send(
-                ScriptMsg::RefcountCleanup(TrustedReference(self.ptr)));
+                ScriptMsg::RefcountCleanup(TrustedReference(self.ptr))).unwrap();
         }
     }
 }
diff --git a/components/script/dom/dedicatedworkerglobalscope.rs b/components/script/dom/dedicatedworkerglobalscope.rs
index 32314d8fc8a..ea16903fd8f 100644
--- a/components/script/dom/dedicatedworkerglobalscope.rs
+++ b/components/script/dom/dedicatedworkerglobalscope.rs
@@ -49,8 +49,8 @@ pub struct SendableWorkerScriptChan {
 }
 
 impl ScriptChan for SendableWorkerScriptChan {
-    fn send(&self, msg: ScriptMsg) {
-        self.sender.send((self.worker.clone(), msg)).unwrap();
+    fn send(&self, msg: ScriptMsg) -> Result<(), ()> {
+        return self.sender.send((self.worker.clone(), msg)).map_err(|_| ());
     }
 
     fn clone(&self) -> Box<ScriptChan + Send> {
@@ -147,7 +147,7 @@ impl DedicatedWorkerGlobalScope {
                 Err(_) => {
                     println!("error loading script {}", worker_url.serialize());
                     parent_sender.send(ScriptMsg::RunnableMsg(
-                        box WorkerEventHandler::new(worker)));
+                        box WorkerEventHandler::new(worker))).unwrap();
                     return;
                 }
                 Ok((metadata, bytes)) => {
@@ -235,7 +235,7 @@ impl<'a> PrivateDedicatedWorkerGlobalScopeHelpers for JSRef<'a, DedicatedWorkerG
         let col_num = errorevent.Colno();
         let worker = self.worker.borrow().as_ref().unwrap().clone();
         self.parent_sender.send(ScriptMsg::WorkerDispatchErrorEvent(worker, msg, file_name,
-                                                                    line_num, col_num));
+                                                                    line_num, col_num)).unwrap();
  }
 }
 
@@ -244,7 +244,7 @@ impl<'a> DedicatedWorkerGlobalScopeMethods for JSRef<'a, DedicatedWorkerGlobalSc
         let data = try!(StructuredCloneData::write(cx, message));
         let worker = self.worker.borrow().as_ref().unwrap().clone();
         self.parent_sender.send(ScriptMsg::RunnableMsg(
-            box WorkerMessageHandler::new(worker, data)));
+            box WorkerMessageHandler::new(worker, data))).unwrap();
         Ok(())
     }
 
diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index be6f1fc9fcb..ddc8d42b661 100644
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -215,7 +215,7 @@ impl<'a> HTMLFormElementHelpers for JSRef<'a, HTMLFormElement> {
         }
 
         // This is wrong. https://html.spec.whatwg.org/multipage/forms.html#planned-navigation
-        win.r().script_chan().send(ScriptMsg::TriggerLoad(win.r().page().id, load_data));
+        win.r().script_chan().send(ScriptMsg::TriggerLoad(win.r().page().id, load_data)).unwrap();
     }
 
     fn get_form_dataset<'b>(self, submitter: Option<FormSubmitter<'b>>) -> Vec<FormDatum> {
diff --git a/components/script/dom/htmlscriptelement.rs b/components/script/dom/htmlscriptelement.rs
index ee3e85f6ed1..662e88f02e1 100644
--- a/components/script/dom/htmlscriptelement.rs
+++ b/components/script/dom/htmlscriptelement.rs
@@ -257,7 +257,7 @@ impl<'a> HTMLScriptElementHelpers for JSRef<'a, HTMLScriptElement> {
             ScriptOrigin::Internal => {
                 let chan = window.script_chan();
                 let handler = Trusted::new(window.get_cx(), self, chan.clone());
-                chan.send(ScriptMsg::RunnableMsg(box handler));
+                chan.send(ScriptMsg::RunnableMsg(box handler)).unwrap();
             }
         }
     }
@@ -268,7 +268,7 @@ impl<'a> HTMLScriptElementHelpers for JSRef<'a, HTMLScriptElement> {
         let window = window.r();
         let chan = window.script_chan();
         let handler = Trusted::new(window.get_cx(), self, chan.clone());
-        chan.send(ScriptMsg::RunnableMsg(box handler));
+        chan.send(ScriptMsg::RunnableMsg(box handler)).unwrap();
     }
 
     fn dispatch_load_event(self) {
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index fcc56776c8d..ded3ba24303 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -197,7 +197,7 @@ impl<'a> WindowMethods for JSRef<'a, Window> {
     }
 
     fn Close(self) {
-        self.script_chan.send(ScriptMsg::ExitWindow(self.page.id.clone()));
+        self.script_chan.send(ScriptMsg::ExitWindow(self.page.id.clone())).unwrap();
     }
 
     fn Document(self) -> Temporary<Document> {
@@ -387,10 +387,10 @@ impl<'a> WindowHelpers for JSRef<'a, Window> {
         let url = url.unwrap();
         match url.fragment {
             Some(fragment) => {
-                self.script_chan.send(ScriptMsg::TriggerFragment(self.page.id, fragment));
+                self.script_chan.send(ScriptMsg::TriggerFragment(self.page.id, fragment)).unwrap();
             },
             None => {
-                self.script_chan.send(ScriptMsg::TriggerLoad(self.page.id, LoadData::new(url)));
+                self.script_chan.send(ScriptMsg::TriggerLoad(self.page.id, LoadData::new(url))).unwrap();
             }
         }
     }
diff --git a/components/script/dom/xmlhttprequest.rs b/components/script/dom/xmlhttprequest.rs
index 5bef26a7c84..b8530f5b38a 100644
--- a/components/script/dom/xmlhttprequest.rs
+++ b/components/script/dom/xmlhttprequest.rs
@@ -220,7 +220,7 @@ impl XMLHttpRequest {
                     xhr.process_partial_response(msg);
                 },
                 SyncOrAsync::Async(ref addr, ref script_chan) => {
-                    script_chan.send(ScriptMsg::RunnableMsg(box XHRProgressHandler::new(addr.clone(), msg)));
+                    script_chan.send(ScriptMsg::RunnableMsg(box XHRProgressHandler::new(addr.clone(), msg))).unwrap();
                 }
             }
         }
diff --git a/components/script/script_task.rs b/components/script/script_task.rs
index 3612b126a9d..939955a64f0 100644
--- a/components/script/script_task.rs
+++ b/components/script/script_task.rs
@@ -15,7 +15,6 @@ use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
 use dom::bindings::codegen::InheritTypes::{ElementCast, EventTargetCast, HTMLIFrameElementCast, NodeCast, EventCast};
 use dom::bindings::conversions::FromJSValConvertible;
 use dom::bindings::conversions::StringificationBehavior;
-use dom::bindings::global::GlobalRef;
 use dom::bindings::js::{JS, JSRef, Temporary, OptionalRootable, RootedReference};
 use dom::bindings::js::{RootCollection, RootCollectionPtr};
 use dom::bindings::refcounted::{LiveDOMReferences, Trusted, TrustedReference};
@@ -24,7 +23,7 @@ use dom::bindings::trace::JSTraceable;
 use dom::bindings::utils::{wrap_for_same_compartment, pre_wrap};
 use dom::document::{Document, IsHTMLDocument, DocumentHelpers, DocumentProgressHandler, DocumentProgressTask, DocumentSource};
 use dom::element::{Element, ActivationElementHelpers};
-use dom::event::{Event, EventHelpers, EventBubbles, EventCancelable};
+use dom::event::{Event, EventHelpers};
 use dom::uievent::UIEvent;
 use dom::eventtarget::EventTarget;
 use dom::htmliframeelement::HTMLIFrameElement;
@@ -86,6 +85,7 @@ 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};
@@ -135,7 +135,7 @@ 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>;
 }
@@ -145,9 +145,9 @@ 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> {
@@ -898,7 +898,7 @@ 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
@@ -906,7 +906,7 @@ 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();
 
diff --git a/components/script/timers.rs b/components/script/timers.rs
index 8f361ebcb7b..0b8d7117022 100644
--- a/components/script/timers.rs
+++ b/components/script/timers.rs
@@ -149,7 +149,10 @@ impl TimerManager {
                 let id = select.wait();
                 if id == timeout_handle.id() {
                     timeout_port.recv().unwrap();
-                    script_chan.send(ScriptMsg::FireTimer(source, TimerId(handle)));
+                    if script_chan.send(ScriptMsg::FireTimer(source, TimerId(handle))).is_err() {
+                        break;
+                    }
+
                     if is_interval == IsInterval::NonInterval {
                         break;
                     }