Auto merge of #12468 - asajeffrey:constellation-remove-panic-channel, r=emilio

Removed panic channel, replaced by integrated logging and issue reporting

<!-- Please describe your changes on the following line: -->

Remove the previous ad hoc panic channel, replace it by an integrated logging and panicking mechanism, including crash reporting. All thread panics are now reported, not just content threads.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #11838
- [X] These changes do not require tests because we don't test error reporting

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/12468)
<!-- Reviewable:end -->

5 files changed, 12 insertions, 36 deletions

diff --git a/components/script/dom/bindings/global.rs b/components/script/dom/bindings/global.rs
index 5adcbb67818..fe81b8a14de 100644
--- a/components/script/dom/bindings/global.rs
+++ b/components/script/dom/bindings/global.rs
@@ -18,7 +18,7 @@ use ipc_channel::ipc::IpcSender;
 use js::jsapi::{CurrentGlobalOrNull, GetGlobalForObjectCrossCompartment};
 use js::jsapi::{JSContext, JSObject, JS_GetClass, MutableHandleValue};
 use js::{JSCLASS_IS_DOMJSCLASS, JSCLASS_IS_GLOBAL};
-use msg::constellation_msg::{PipelineId, PanicMsg};
+use msg::constellation_msg::PipelineId;
 use net_traits::filemanager_thread::FileManagerThreadMsg;
 use net_traits::{ResourceThreads, CoreResourceThread, IpcSend};
 use profile_traits::{mem, time};
@@ -283,14 +283,6 @@ impl<'a> GlobalRef<'a> {
         }
     }
 
-    /// Returns an `IpcSender` to report panics on.
-    pub fn panic_chan(&self) -> &IpcSender<PanicMsg> {
-        match *self {
-            GlobalRef::Window(ref window) => window.panic_chan(),
-            GlobalRef::Worker(ref worker) => worker.panic_chan(),
-        }
-    }
-
     /// Returns a wrapper for runnables to ensure they are cancelled if the global
     /// is being destroyed.
     pub fn get_runnable_wrapper(&self) -> RunnableWrapper {
diff --git a/components/script/dom/dedicatedworkerglobalscope.rs b/components/script/dom/dedicatedworkerglobalscope.rs
index cf5537676e0..b65fd72ab62 100644
--- a/components/script/dom/dedicatedworkerglobalscope.rs
+++ b/components/script/dom/dedicatedworkerglobalscope.rs
@@ -38,8 +38,8 @@ use std::sync::atomic::AtomicBool;
 use std::sync::mpsc::{Receiver, RecvError, Select, Sender, channel};
 use std::sync::{Arc, Mutex};
 use url::Url;
-use util::thread::spawn_named_with_send_on_panic;
-use util::thread_state::{IN_WORKER, SCRIPT};
+use util::thread::spawn_named;
+use util::thread_state;
 
 /// Set the `worker` field of a related DedicatedWorkerGlobalScope object to a particular
 /// value for the duration of this object's lifetime. This ensures that the related Worker
@@ -161,8 +161,10 @@ impl DedicatedWorkerGlobalScope {
                             closing: Arc<AtomicBool>) {
         let serialized_worker_url = worker_url.to_string();
         let name = format!("WebWorker for {}", serialized_worker_url);
-        let panic_chan = init.panic_chan.clone();
-        spawn_named_with_send_on_panic(name, SCRIPT | IN_WORKER, move || {
+        spawn_named(name, move || {
+            thread_state::initialize(thread_state::SCRIPT | thread_state::IN_WORKER);
+            PipelineId::install(id);
+
             let roots = RootCollection::new();
             let _stack_roots_tls = StackRootTLS::new(&roots);
             let (url, source) = match load_whole_resource(LoadContext::Script,
@@ -225,7 +227,7 @@ impl DedicatedWorkerGlobalScope {
                     global.handle_event(event);
                 }
             }, reporter_name, parent_sender, CommonScriptMsg::CollectReports);
-        }, Some(id.clone()), panic_chan);
+        });
     }
 
     pub fn script_chan(&self) -> Box<ScriptChan + Send> {
diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index 1b2001c08df..efd33eecf54 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -353,8 +353,8 @@ unsafe fn build_mozbrowser_event_detail(event: MozBrowserEvent,
         MozBrowserEvent::Error(error_type, description, report) => {
             BrowserElementErrorEventDetail {
                 type_: Some(DOMString::from(error_type.name())),
-                description: description.map(DOMString::from),
-                report: report.map(DOMString::from),
+                description: Some(DOMString::from(description)),
+                report: Some(DOMString::from(report)),
                 version: Some(DOMString::from_string(servo_version().into())),
             }.to_jsval(cx, rval);
         },
diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 07509a92e4a..b4984bb2a4a 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -45,7 +45,7 @@ use js::jsapi::{JS_GetRuntime, JS_GC, MutableHandleValue, SetWindowProxy};
 use js::rust::CompileOptionsWrapper;
 use js::rust::Runtime;
 use libc;
-use msg::constellation_msg::{FrameType, LoadData, PanicMsg, PipelineId, SubpageId, WindowSizeType};
+use msg::constellation_msg::{FrameType, LoadData, PipelineId, SubpageId, WindowSizeType};
 use net_traits::ResourceThreads;
 use net_traits::bluetooth_thread::BluetoothMethodMsg;
 use net_traits::image_cache_thread::{ImageCacheChan, ImageCacheThread};
@@ -266,9 +266,6 @@ pub struct Window {
 
     /// A list of scroll offsets for each scrollable element.
     scroll_offsets: DOMRefCell<HashMap<UntrustedNodeAddress, Point2D<f32>>>,
-
-    #[ignore_heap_size_of = "Defined in ipc-channel"]
-    panic_chan: IpcSender<PanicMsg>,
 }
 
 impl Window {
@@ -1424,10 +1421,6 @@ impl Window {
         &self.scheduler_chan
     }
 
-    pub fn panic_chan(&self) -> &IpcSender<PanicMsg> {
-        &self.panic_chan
-    }
-
     pub fn schedule_callback(&self, callback: OneshotTimerCallback, duration: MsDuration) -> OneshotTimerHandle {
         self.timers.schedule_callback(callback,
                                       duration,
@@ -1623,7 +1616,6 @@ impl Window {
                constellation_chan: IpcSender<ConstellationMsg>,
                control_chan: IpcSender<ConstellationControlMsg>,
                scheduler_chan: IpcSender<TimerEventRequest>,
-               panic_chan: IpcSender<PanicMsg>,
                timer_event_chan: IpcSender<TimerEvent>,
                layout_chan: Sender<Msg>,
                id: PipelineId,
@@ -1693,7 +1685,6 @@ impl Window {
             ignore_further_async_events: Arc::new(AtomicBool::new(false)),
             error_reporter: error_reporter,
             scroll_offsets: DOMRefCell::new(HashMap::new()),
-            panic_chan: panic_chan,
         };
 
         WindowBinding::Wrap(runtime.cx(), win)
diff --git a/components/script/dom/workerglobalscope.rs b/components/script/dom/workerglobalscope.rs
index cd8476b49d6..154705fe145 100644
--- a/components/script/dom/workerglobalscope.rs
+++ b/components/script/dom/workerglobalscope.rs
@@ -23,7 +23,7 @@ use ipc_channel::ipc::IpcSender;
 use js::jsapi::{HandleValue, JSContext, JSRuntime};
 use js::jsval::UndefinedValue;
 use js::rust::Runtime;
-use msg::constellation_msg::{PipelineId, ReferrerPolicy, PanicMsg};
+use msg::constellation_msg::{PipelineId, ReferrerPolicy};
 use net_traits::{LoadContext, ResourceThreads, load_whole_resource};
 use net_traits::{LoadOrigin, IpcSend};
 use profile_traits::{mem, time};
@@ -58,7 +58,6 @@ pub fn prepare_workerscope_init(global: GlobalRef,
             time_profiler_chan: global.time_profiler_chan().clone(),
             from_devtools_sender: devtools_sender,
             constellation_chan: global.constellation_chan().clone(),
-            panic_chan: global.panic_chan().clone(),
             scheduler_chan: global.scheduler_chan().clone(),
             worker_id: worker_id
         };
@@ -110,9 +109,6 @@ pub struct WorkerGlobalScope {
 
     #[ignore_heap_size_of = "Defined in std"]
     scheduler_chan: IpcSender<TimerEventRequest>,
-
-    #[ignore_heap_size_of = "Defined in ipc-channel"]
-    panic_chan: IpcSender<PanicMsg>,
 }
 
 impl WorkerGlobalScope {
@@ -144,7 +140,6 @@ impl WorkerGlobalScope {
             devtools_wants_updates: Cell::new(false),
             constellation_chan: init.constellation_chan,
             scheduler_chan: init.scheduler_chan,
-            panic_chan: init.panic_chan,
         }
     }
 
@@ -221,10 +216,6 @@ impl WorkerGlobalScope {
         worker_id
     }
 
-    pub fn panic_chan(&self) -> &IpcSender<PanicMsg> {
-        &self.panic_chan
-    }
-
     pub fn get_runnable_wrapper(&self) -> RunnableWrapper {
         RunnableWrapper {
             cancelled: self.closing.clone().unwrap(),