servo: Merge #8599 - compositing: Split Servo up into multiple sandboxed processes (from jdm:e10s-redux); r=metajack

Multiprocess mode is enabled with the `-M` switch, and sandboxing is
enabled with the `-S` switch.

Rebase of #6884.

Source-Repo: https://github.com/servo/servo
Source-Revision: 8b39b9afed6ef8a3d7d3e6609fd301a37825d3e1

servo/components/script/script_task.rs

@@ -104,7 +104,7 @@ use time::{Tm, now};
 use url::{Url, UrlParser};
 use util::opts;
 use util::str::DOMString;
-use util::task::spawn_named_with_send_on_failure;
+use util::task;
 use util::task_state;
 use webdriver_handlers;
 
@@ -232,8 +232,9 @@ pub enum ScriptTaskEventCategory {
     Resize,
     ScriptEvent,
     TimerEvent,
-    UpdateReplacedElement,
     SetViewport,
+    StylesheetLoad,
+    UpdateReplacedElement,
     WebSocketEvent,
     WorkerEvent,
 }
@@ -396,7 +397,7 @@ pub struct ScriptTask {
     chan: MainThreadScriptChan,
 
     /// A channel to hand out to tasks that need to respond to a message from the script task.
-    control_chan: Sender<ConstellationControlMsg>,
+    control_chan: IpcSender<ConstellationControlMsg>,
 
     /// The port on which the constellation and layout tasks can communicate with the
     /// script task.
@@ -438,6 +439,8 @@ pub struct ScriptTask {
     scheduler_chan: IpcSender<TimerEventRequest>,
     timer_event_chan: Sender<TimerEvent>,
     timer_event_port: Receiver<TimerEvent>,
+
+    content_process_shutdown_chan: IpcSender<()>,
 }
 
 /// In the event of task failure, all data on the stack runs its destructor. However, there
@@ -484,7 +487,8 @@ impl ScriptTaskFactory for ScriptTask {
         ScriptLayoutChan::new(chan, port)
     }
 
-    fn clone_layout_channel(_phantom: Option<&mut ScriptTask>, pair: &OpaqueScriptLayoutChannel) -> Box<Any + Send> {
+    fn clone_layout_channel(_phantom: Option<&mut ScriptTask>, pair: &OpaqueScriptLayoutChannel)
+                            -> Box<Any + Send> {
         box pair.sender() as Box<Any + Send>
     }
 
@@ -496,9 +500,10 @@ impl ScriptTaskFactory for ScriptTask {
         let (script_chan, script_port) = channel();
         let layout_chan = LayoutChan(layout_chan.sender());
         let failure_info = state.failure_info;
-        spawn_named_with_send_on_failure(format!("ScriptTask {:?}", state.id), task_state::SCRIPT, move || {
+        task::spawn_named_with_send_on_failure(format!("ScriptTask {:?}", state.id),
+                                               task_state::SCRIPT,
+                                               move || {
             PipelineNamespace::install(state.pipeline_namespace_id);
-
             let roots = RootCollection::new();
             let _stack_roots_tls = StackRootTLS::new(&roots);
             let chan = MainThreadScriptChan(script_chan);
@@ -524,6 +529,7 @@ impl ScriptTaskFactory for ScriptTask {
             let reporter_name = format!("script-reporter-{}", id);
             mem_profiler_chan.run_with_memory_reporting(|| {
                 script_task.start();
+                let _ = script_task.content_process_shutdown_chan.send(());
             }, reporter_name, channel_for_reporter, CommonScriptMsg::CollectReports);
 
             // This must always be the very last operation performed before the task completes
@@ -636,6 +642,9 @@ impl ScriptTask {
 
         let (timer_event_chan, timer_event_port) = channel();
 
+        // Ask the router to proxy IPC messages from the control port to us.
+        let control_port = ROUTER.route_ipc_receiver_to_new_mpsc_receiver(state.control_port);
+
         ScriptTask {
             page: DOMRefCell::new(None),
             incomplete_loads: DOMRefCell::new(vec!()),
@@ -650,7 +659,7 @@ impl ScriptTask {
             port: port,
             chan: chan,
             control_chan: state.control_chan,
-            control_port: state.control_port,
+            control_port: control_port,
             constellation_chan: state.constellation_chan,
             compositor: DOMRefCell::new(state.compositor),
             time_profiler_chan: state.time_profiler_chan,
@@ -667,6 +676,8 @@ impl ScriptTask {
             scheduler_chan: state.scheduler_chan,
             timer_event_chan: timer_event_chan,
             timer_event_port: timer_event_port,
+
+            content_process_shutdown_chan: state.content_process_shutdown_chan,
         }
     }
 
@@ -940,7 +951,10 @@ impl ScriptTask {
                 ScriptTaskEventCategory::NetworkEvent => ProfilerCategory::ScriptNetworkEvent,
                 ScriptTaskEventCategory::Resize => ProfilerCategory::ScriptResize,
                 ScriptTaskEventCategory::ScriptEvent => ProfilerCategory::ScriptEvent,
-                ScriptTaskEventCategory::UpdateReplacedElement => ProfilerCategory::ScriptUpdateReplacedElement,
+                ScriptTaskEventCategory::UpdateReplacedElement => {
+                    ProfilerCategory::ScriptUpdateReplacedElement
+                }
+                ScriptTaskEventCategory::StylesheetLoad => ProfilerCategory::ScriptStylesheetLoad,
                 ScriptTaskEventCategory::SetViewport => ProfilerCategory::ScriptSetViewport,
                 ScriptTaskEventCategory::TimerEvent => ProfilerCategory::ScriptTimerEvent,
                 ScriptTaskEventCategory::WebSocketEvent => ProfilerCategory::ScriptWebSocketEvent,
@@ -1185,6 +1199,7 @@ impl ScriptTask {
             failure,
             pipeline_port,
             layout_shutdown_chan,
+            content_process_shutdown_chan,
         } = new_layout_info;
 
         let layout_pair = ScriptTask::create_layout_channel(None::<&mut ScriptTask>);
@@ -1204,6 +1219,7 @@ impl ScriptTask {
             script_chan: self.control_chan.clone(),
             image_cache_task: self.image_cache_task.clone(),
             layout_shutdown_chan: layout_shutdown_chan,
+            content_process_shutdown_chan: content_process_shutdown_chan,
         };
 
         let page = self.root_page();