Merge branch 'master' into js-modules

# Conflicts:
#	modules/libpref/init/all.js

17 files changed, 200 insertions, 196 deletions

diff --git a/dom/workers/RuntimeService.cpp b/dom/workers/RuntimeService.cpp
index e1910536f..19c4ded2a 100644
--- a/dom/workers/RuntimeService.cpp
+++ b/dom/workers/RuntimeService.cpp
@@ -30,7 +30,6 @@
 #include "mozilla/AsyncEventDispatcher.h"
 #include "mozilla/Atomics.h"
 #include "mozilla/CycleCollectedJSContext.h"
-#include "mozilla/Telemetry.h"
 #include "mozilla/TimeStamp.h"
 #include "mozilla/dom/asmjscache/AsmJSCache.h"
 #include "mozilla/dom/AtomList.h"
@@ -989,7 +988,7 @@ Wrap(JSContext *cx, JS::HandleObject existing, JS::HandleObject obj)
   }
 
   if (existing) {
-    js::Wrapper::Renew(cx, existing, obj, wrapper);
+    js::Wrapper::Renew(existing, obj, wrapper);
   }
   return js::Wrapper::New(cx, obj, wrapper);
 }
@@ -1531,10 +1530,8 @@ RuntimeService::RegisterWorker(WorkerPrivate* aWorkerPrivate)
 
   const bool isServiceWorker = aWorkerPrivate->IsServiceWorker();
   const bool isSharedWorker = aWorkerPrivate->IsSharedWorker();
-  const bool isDedicatedWorker = aWorkerPrivate->IsDedicatedWorker();
   if (isServiceWorker) {
     AssertIsOnMainThread();
-    Telemetry::Accumulate(Telemetry::SERVICE_WORKER_SPAWN_ATTEMPTS, 1);
   }
 
   nsCString sharedWorkerScriptSpec;
@@ -1586,14 +1583,6 @@ RuntimeService::RegisterWorker(WorkerPrivate* aWorkerPrivate)
       // Worker spawn gets queued due to hitting max workers per domain
       // limit so let's log a warning.
       WorkerPrivate::ReportErrorToConsole("HittingMaxWorkersPerDomain2");
-
-      if (isServiceWorker) {
-        Telemetry::Accumulate(Telemetry::SERVICE_WORKER_SPAWN_GETS_QUEUED, 1);
-      } else if (isSharedWorker) {
-        Telemetry::Accumulate(Telemetry::SHARED_WORKER_SPAWN_GETS_QUEUED, 1);
-      } else if (isDedicatedWorker) {
-        Telemetry::Accumulate(Telemetry::DEDICATED_WORKER_SPAWN_GETS_QUEUED, 1);
-      }
     }
     else if (parent) {
       domainInfo->mChildWorkerCount++;
@@ -1669,7 +1658,6 @@ RuntimeService::RegisterWorker(WorkerPrivate* aWorkerPrivate)
 
   if (isServiceWorker) {
     AssertIsOnMainThread();
-    Telemetry::Accumulate(Telemetry::SERVICE_WORKER_WAS_SPAWNED, 1);
   }
   return true;
 }
@@ -1766,8 +1754,6 @@ RuntimeService::UnregisterWorker(WorkerPrivate* aWorkerPrivate)
 
   if (aWorkerPrivate->IsServiceWorker()) {
     AssertIsOnMainThread();
-    Telemetry::AccumulateTimeDelta(Telemetry::SERVICE_WORKER_LIFE_TIME,
-                                   aWorkerPrivate->CreationTimeStamp());
   }
 
   if (aWorkerPrivate->IsSharedWorker() ||
diff --git a/dom/workers/ServiceWorkerClient.cpp b/dom/workers/ServiceWorkerClient.cpp
index 660512a5f..6ed3a6ea4 100644
--- a/dom/workers/ServiceWorkerClient.cpp
+++ b/dom/workers/ServiceWorkerClient.cpp
@@ -224,7 +224,7 @@ ServiceWorkerClient::PostMessage(JSContext* aCx, JS::Handle<JS::Value> aMessage,
     return;
   }
 
-  aRv = workerPrivate->DispatchToMainThread(runnable.forget());
+  aRv = NS_DispatchToMainThread(runnable);
   if (NS_WARN_IF(aRv.Failed())) {
     return;
   }
diff --git a/dom/workers/ServiceWorkerClients.cpp b/dom/workers/ServiceWorkerClients.cpp
index 11f864443..38f49e355 100644
--- a/dom/workers/ServiceWorkerClients.cpp
+++ b/dom/workers/ServiceWorkerClients.cpp
@@ -753,7 +753,7 @@ ServiceWorkerClients::Get(const nsAString& aClientId, ErrorResult& aRv)
 
   RefPtr<GetRunnable> r =
     new GetRunnable(promiseProxy, aClientId);
-  MOZ_ALWAYS_SUCCEEDS(workerPrivate->DispatchToMainThread(r.forget()));
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(r));
   return promise.forget();
 }
 
@@ -789,7 +789,7 @@ ServiceWorkerClients::MatchAll(const ClientQueryOptions& aOptions,
     new MatchAllRunnable(promiseProxy,
                          NS_ConvertUTF16toUTF8(scope),
                          aOptions.mIncludeUncontrolled);
-  MOZ_ALWAYS_SUCCEEDS(workerPrivate->DispatchToMainThread(r.forget()));
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(r));
   return promise.forget();
 }
 
@@ -830,7 +830,7 @@ ServiceWorkerClients::OpenWindow(const nsAString& aUrl,
 
   RefPtr<OpenWindowRunnable> r = new OpenWindowRunnable(promiseProxy,
                                                         aUrl, scope);
-  MOZ_ALWAYS_SUCCEEDS(workerPrivate->DispatchToMainThread(r.forget()));
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(r));
 
   return promise.forget();
 }
@@ -859,6 +859,6 @@ ServiceWorkerClients::Claim(ErrorResult& aRv)
   RefPtr<ClaimRunnable> runnable =
     new ClaimRunnable(promiseProxy, NS_ConvertUTF16toUTF8(scope));
 
-  MOZ_ALWAYS_SUCCEEDS(workerPrivate->DispatchToMainThread(runnable.forget()));
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(runnable));
   return promise.forget();
 }
diff --git a/dom/workers/ServiceWorkerEvents.cpp b/dom/workers/ServiceWorkerEvents.cpp
index 1f79e2c92..8b375c635 100644
--- a/dom/workers/ServiceWorkerEvents.cpp
+++ b/dom/workers/ServiceWorkerEvents.cpp
@@ -400,13 +400,7 @@ void RespondWithCopyComplete(void* aClosure, nsresult aStatus)
                                data->mScriptSpec,
                                data->mResponseURLSpec);
   }
-  // In theory this can happen after the worker thread is terminated.
-  WorkerPrivate* worker = GetCurrentThreadWorkerPrivate();
-  if (worker) {
-    MOZ_ALWAYS_SUCCEEDS(worker->DispatchToMainThread(event.forget()));
-  } else {
-    MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(event.forget()));
-  }
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(event));
 }
 
 namespace {
@@ -734,13 +728,7 @@ RespondWithHandler::CancelRequest(nsresult aStatus)
 {
   nsCOMPtr<nsIRunnable> runnable =
     new CancelChannelRunnable(mInterceptedChannel, mRegistration, aStatus);
-  // Note, this may run off the worker thread during worker termination.
-  WorkerPrivate* worker = GetCurrentThreadWorkerPrivate();
-  if (worker) {
-    MOZ_ALWAYS_SUCCEEDS(worker->DispatchToMainThread(runnable.forget()));
-  } else {
-    MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(runnable.forget()));
-  }
+  NS_DispatchToMainThread(runnable);
   mRequestWasHandled = true;
 }
 
@@ -873,8 +861,8 @@ public:
       mColumn = column;
     }
 
-    MOZ_ALWAYS_SUCCEEDS(mWorkerPrivate->DispatchToMainThread(
-        NewRunnableMethod(this, &WaitUntilHandler::ReportOnMainThread)));
+    MOZ_ALWAYS_SUCCEEDS(
+      NS_DispatchToMainThread(NewRunnableMethod(this, &WaitUntilHandler::ReportOnMainThread)));
   }
 
   void
diff --git a/dom/workers/ServiceWorkerManager.cpp b/dom/workers/ServiceWorkerManager.cpp
index a66df0731..a8f191f2e 100644
--- a/dom/workers/ServiceWorkerManager.cpp
+++ b/dom/workers/ServiceWorkerManager.cpp
@@ -33,7 +33,6 @@
 #include "mozilla/ClearOnShutdown.h"
 #include "mozilla/ErrorNames.h"
 #include "mozilla/LoadContext.h"
-#include "mozilla/Telemetry.h"
 #include "mozilla/dom/BindingUtils.h"
 #include "mozilla/dom/ContentParent.h"
 #include "mozilla/dom/DOMError.h"
@@ -676,7 +675,6 @@ ServiceWorkerManager::Register(mozIDOMWindow* aWindow,
   queue->ScheduleJob(job);
 
   AssertIsOnMainThread();
-  Telemetry::Accumulate(Telemetry::SERVICE_WORKER_REGISTRATIONS, 1);
 
   promise.forget(aPromise);
   return NS_OK;
@@ -2180,7 +2178,6 @@ ServiceWorkerManager::StartControllingADocument(ServiceWorkerRegistrationInfo* a
   if (!aDocumentId.IsEmpty()) {
     aDoc->SetId(aDocumentId);
   }
-  Telemetry::Accumulate(Telemetry::SERVICE_WORKER_CONTROLLED_DOCUMENTS, 1);
 }
 
 void
diff --git a/dom/workers/ServiceWorkerPrivate.cpp b/dom/workers/ServiceWorkerPrivate.cpp
index 24b2e11e6..23ae3b366 100644
--- a/dom/workers/ServiceWorkerPrivate.cpp
+++ b/dom/workers/ServiceWorkerPrivate.cpp
@@ -214,7 +214,7 @@ private:
     mDone = true;
 #endif
     mCallback->SetResult(aResult);
-    MOZ_ALWAYS_SUCCEEDS(mWorkerPrivate->DispatchToMainThread(mCallback));
+    MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(mCallback));
   }
 };
 
@@ -500,7 +500,7 @@ public:
     if (mRegistration) {
       nsCOMPtr<nsIRunnable> runnable =
         new RegistrationUpdateRunnable(mRegistration, true /* time check */);
-      aWorkerPrivate->DispatchToMainThread(runnable.forget());
+      NS_DispatchToMainThread(runnable.forget());
     }
 
     ExtendableEventWorkerRunnable::PostRun(aCx, aWorkerPrivate, aRunResult);
@@ -541,7 +541,7 @@ public:
   Cancel() override
   {
     mCallback->SetResult(false);
-    MOZ_ALWAYS_SUCCEEDS(mWorkerPrivate->DispatchToMainThread(mCallback));
+    MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(mCallback));
 
     return WorkerRunnable::Cancel();
   }
@@ -637,7 +637,7 @@ public:
     mDone = true;
 
     mCallback->SetResult(aResult);
-    nsresult rv = mWorkerPrivate->DispatchToMainThread(mCallback);
+    nsresult rv = NS_DispatchToMainThread(mCallback);
     if (NS_WARN_IF(NS_FAILED(rv))) {
       NS_RUNTIMEABORT("Failed to dispatch life cycle event handler.");
     }
@@ -768,7 +768,6 @@ public:
 
   void Report(uint16_t aReason = nsIPushErrorReporter::DELIVERY_INTERNAL_ERROR)
   {
-    WorkerPrivate* workerPrivate = mWorkerPrivate;
     mWorkerPrivate->AssertIsOnWorkerThread();
     mWorkerPrivate = nullptr;
 
@@ -780,7 +779,7 @@ public:
       NewRunnableMethod<uint16_t>(this,
         &PushErrorReporter::ReportOnMainThread, aReason);
     MOZ_ALWAYS_TRUE(NS_SUCCEEDED(
-      workerPrivate->DispatchToMainThread(runnable.forget())));
+      NS_DispatchToMainThread(runnable.forget())));
   }
 
   void ReportOnMainThread(uint16_t aReason)
@@ -1434,7 +1433,7 @@ public:
   Cancel() override
   {
     nsCOMPtr<nsIRunnable> runnable = new ResumeRequest(mInterceptedChannel);
-    if (NS_FAILED(mWorkerPrivate->DispatchToMainThread(runnable))) {
+    if (NS_FAILED(NS_DispatchToMainThread(runnable))) {
       NS_WARNING("Failed to resume channel on FetchEventRunnable::Cancel()!\n");
     }
     WorkerRunnable::Cancel();
@@ -1554,7 +1553,7 @@ private:
                                              NS_ERROR_INTERCEPTION_FAILED);
       }
 
-      MOZ_ALWAYS_SUCCEEDS(mWorkerPrivate->DispatchToMainThread(runnable.forget()));
+      MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(runnable));
     }
 
     RefPtr<Promise> waitUntilPromise = event->GetPromise();
diff --git a/dom/workers/ServiceWorkerRegistrar.cpp b/dom/workers/ServiceWorkerRegistrar.cpp
index a4757ea54..7df129c2b 100644
--- a/dom/workers/ServiceWorkerRegistrar.cpp
+++ b/dom/workers/ServiceWorkerRegistrar.cpp
@@ -135,9 +135,6 @@ ServiceWorkerRegistrar::GetRegistrations(
 
   if (firstTime) {
     firstTime = false;
-    Telemetry::AccumulateTimeDelta(
-      Telemetry::SERVICE_WORKER_REGISTRATION_LOADING,
-      startTime);
   }
 }
 
diff --git a/dom/workers/ServiceWorkerRegistration.cpp b/dom/workers/ServiceWorkerRegistration.cpp
index 451bd2be9..b3cda2c10 100644
--- a/dom/workers/ServiceWorkerRegistration.cpp
+++ b/dom/workers/ServiceWorkerRegistration.cpp
@@ -1107,7 +1107,7 @@ ServiceWorkerRegistrationWorkerThread::Update(ErrorResult& aRv)
   }
 
   RefPtr<UpdateRunnable> r = new UpdateRunnable(proxy, mScope);
-  MOZ_ALWAYS_SUCCEEDS(worker->DispatchToMainThread(r.forget()));
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(r));
 
   return promise.forget();
 }
@@ -1139,7 +1139,7 @@ ServiceWorkerRegistrationWorkerThread::Unregister(ErrorResult& aRv)
   }
 
   RefPtr<StartUnregisterRunnable> r = new StartUnregisterRunnable(proxy, mScope);
-  MOZ_ALWAYS_SUCCEEDS(worker->DispatchToMainThread(r.forget()));
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(r));
 
   return promise.forget();
 }
@@ -1161,7 +1161,7 @@ ServiceWorkerRegistrationWorkerThread::InitListener()
 
   nsCOMPtr<nsIRunnable> r =
     NewRunnableMethod(mListener, &WorkerListener::StartListeningForEvents);
-  MOZ_ALWAYS_SUCCEEDS(worker->DispatchToMainThread(r.forget()));
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(r));
 }
 
 void
@@ -1183,7 +1183,7 @@ ServiceWorkerRegistrationWorkerThread::ReleaseListener()
 
   nsCOMPtr<nsIRunnable> r =
     NewRunnableMethod(mListener, &WorkerListener::StopListeningForEvents);
-  MOZ_ALWAYS_SUCCEEDS(mWorkerPrivate->DispatchToMainThread(r.forget()));
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(r));
 
   mListener = nullptr;
   mWorkerPrivate = nullptr;
diff --git a/dom/workers/ServiceWorkerUpdateJob.cpp b/dom/workers/ServiceWorkerUpdateJob.cpp
index 614fe4de5..69877dfe4 100644
--- a/dom/workers/ServiceWorkerUpdateJob.cpp
+++ b/dom/workers/ServiceWorkerUpdateJob.cpp
@@ -408,8 +408,6 @@ ServiceWorkerUpdateJob::ComparisonResult(nsresult aStatus,
     return;
   }
 
-  Telemetry::Accumulate(Telemetry::SERVICE_WORKER_UPDATED, 1);
-
   // Begin step 7 of the Update algorithm to evaluate the new script.
 
   RefPtr<ServiceWorkerInfo> sw =
diff --git a/dom/workers/ServiceWorkerWindowClient.cpp b/dom/workers/ServiceWorkerWindowClient.cpp
index 2ce0603cf..bae747214 100644
--- a/dom/workers/ServiceWorkerWindowClient.cpp
+++ b/dom/workers/ServiceWorkerWindowClient.cpp
@@ -183,7 +183,7 @@ ServiceWorkerWindowClient::Focus(ErrorResult& aRv) const
     if (promiseProxy) {
       RefPtr<ClientFocusRunnable> r = new ClientFocusRunnable(mWindowId,
                                                               promiseProxy);
-      MOZ_ALWAYS_SUCCEEDS(workerPrivate->DispatchToMainThread(r.forget()));
+      MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(r));
     } else {
       promise->MaybeReject(NS_ERROR_DOM_ABORT_ERR);
     }
@@ -549,7 +549,7 @@ ServiceWorkerWindowClient::Navigate(const nsAString& aUrl, ErrorResult& aRv)
   if (promiseProxy) {
     RefPtr<ClientNavigateRunnable> r =
       new ClientNavigateRunnable(mWindowId, aUrl, scope, promiseProxy);
-    MOZ_ALWAYS_SUCCEEDS(workerPrivate->DispatchToMainThread(r.forget()));
+    MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(r));
   } else {
     promise->MaybeReject(NS_ERROR_DOM_ABORT_ERR);
   }
diff --git a/dom/workers/SharedWorker.cpp b/dom/workers/SharedWorker.cpp
index b0eed2def..99bb50339 100644
--- a/dom/workers/SharedWorker.cpp
+++ b/dom/workers/SharedWorker.cpp
@@ -12,7 +12,6 @@
 #include "mozilla/Preferences.h"
 #include "mozilla/dom/MessagePort.h"
 #include "mozilla/dom/SharedWorkerBinding.h"
-#include "mozilla/Telemetry.h"
 #include "nsContentUtils.h"
 #include "nsIClassInfoImpl.h"
 #include "nsIDOMEvent.h"
@@ -73,8 +72,6 @@ SharedWorker::Constructor(const GlobalObject& aGlobal, JSContext* aCx,
     return nullptr;
   }
 
-  Telemetry::Accumulate(Telemetry::SHARED_WORKER_COUNT, 1);
-
   return sharedWorker.forget();
 }
 
diff --git a/dom/workers/WorkerPrivate.cpp b/dom/workers/WorkerPrivate.cpp
index 612090027..27eb570e9 100644
--- a/dom/workers/WorkerPrivate.cpp
+++ b/dom/workers/WorkerPrivate.cpp
@@ -87,6 +87,7 @@
 #include "nsProxyRelease.h"
 #include "nsQueryObject.h"
 #include "nsSandboxFlags.h"
+#include "nsScriptError.h"
 #include "nsUTF8Utils.h"
 #include "prthread.h"
 #include "xpcpublic.h"
@@ -281,27 +282,34 @@ struct WindowAction
 };
 
 void
-LogErrorToConsole(const nsAString& aMessage,
-                  const nsAString& aFilename,
-                  const nsAString& aLine,
-                  uint32_t aLineNumber,
-                  uint32_t aColumnNumber,
-                  uint32_t aFlags,
-                  uint64_t aInnerWindowId)
+LogErrorToConsole(const WorkerErrorReport& aReport, uint64_t aInnerWindowId)
 {
   AssertIsOnMainThread();
 
-  nsCOMPtr<nsIScriptError> scriptError =
-    do_CreateInstance(NS_SCRIPTERROR_CONTRACTID);
+  RefPtr<nsScriptErrorBase> scriptError = new nsScriptError();
   NS_WARNING_ASSERTION(scriptError, "Failed to create script error!");
 
   if (scriptError) {
-    if (NS_FAILED(scriptError->InitWithWindowID(aMessage, aFilename, aLine,
-                                                aLineNumber, aColumnNumber,
-                                                aFlags, "Web Worker",
+    nsAutoCString category("Web Worker");
+    if (NS_FAILED(scriptError->InitWithWindowID(aReport.mMessage,
+                                                aReport.mFilename,
+                                                aReport.mLine,
+                                                aReport.mLineNumber,
+                                                aReport.mColumnNumber,
+                                                aReport.mFlags,
+                                                category,
                                                 aInnerWindowId))) {
       NS_WARNING("Failed to init script error!");
       scriptError = nullptr;
+
+    for (size_t i = 0, len = aReport.mNotes.Length(); i < len; i++) {
+      const WorkerErrorNote& note = aReport.mNotes.ElementAt(i);
+
+      nsScriptErrorNote* noteObject = new nsScriptErrorNote();
+      noteObject->Init(note.mMessage, note.mFilename,
+                       note.mLineNumber, note.mColumnNumber);
+      scriptError->AddNote(noteObject);
+    }
     }
   }
 
@@ -316,23 +324,23 @@ LogErrorToConsole(const nsAString& aMessage,
       }
       NS_WARNING("LogMessage failed!");
     } else if (NS_SUCCEEDED(consoleService->LogStringMessage(
-                                                    aMessage.BeginReading()))) {
+                              aReport.mMessage.BeginReading()))) {
       return;
     }
     NS_WARNING("LogStringMessage failed!");
   }
 
-  NS_ConvertUTF16toUTF8 msg(aMessage);
-  NS_ConvertUTF16toUTF8 filename(aFilename);
+  NS_ConvertUTF16toUTF8 msg(aReport.mMessage);
+  NS_ConvertUTF16toUTF8 filename(aReport.mFilename);
 
   static const char kErrorString[] = "JS error in Web Worker: %s [%s:%u]";
 
 #ifdef ANDROID
   __android_log_print(ANDROID_LOG_INFO, "Gecko", kErrorString, msg.get(),
-                      filename.get(), aLineNumber);
+                      filename.get(), aReport.mLineNumber);
 #endif
 
-  fprintf(stderr, kErrorString, msg.get(), filename.get(), aLineNumber);
+  fprintf(stderr, kErrorString, msg.get(), filename.get(), aReport.mLineNumber);
   fflush(stderr);
 }
 
@@ -404,7 +412,7 @@ private:
 
     RefPtr<MainThreadReleaseRunnable> runnable =
       new MainThreadReleaseRunnable(doomed, loadGroupToCancel);
-    if (NS_FAILED(mWorkerPrivate->DispatchToMainThread(runnable.forget()))) {
+    if (NS_FAILED(NS_DispatchToMainThread(runnable))) {
       NS_WARNING("Failed to dispatch, going to leak!");
     }
 
@@ -536,10 +544,7 @@ private:
     }
 
     if (aWorkerPrivate->IsSharedWorker()) {
-      aWorkerPrivate->BroadcastErrorToSharedWorkers(aCx, EmptyString(),
-                                                    EmptyString(),
-                                                    EmptyString(), 0, 0,
-                                                    JSREPORT_ERROR,
+      aWorkerPrivate->BroadcastErrorToSharedWorkers(aCx, nullptr,
                                                     /* isErrorEvent */ false);
       return true;
     }
@@ -1060,15 +1065,7 @@ private:
 
 class ReportErrorRunnable final : public WorkerRunnable
 {
-  nsString mMessage;
-  nsString mFilename;
-  nsString mLine;
-  uint32_t mLineNumber;
-  uint32_t mColumnNumber;
-  uint32_t mFlags;
-  uint32_t mErrorNumber;
-  JSExnType mExnType;
-  bool mMutedError;
+  WorkerErrorReport mReport;
 
 public:
   // aWorkerPrivate is the worker thread we're on (or the main thread, if null)
@@ -1077,11 +1074,7 @@ public:
   static void
   ReportError(JSContext* aCx, WorkerPrivate* aWorkerPrivate,
               bool aFireAtScope, WorkerPrivate* aTarget,
-              const nsString& aMessage, const nsString& aFilename,
-              const nsString& aLine, uint32_t aLineNumber,
-              uint32_t aColumnNumber, uint32_t aFlags,
-              uint32_t aErrorNumber, JSExnType aExnType,
-              bool aMutedError, uint64_t aInnerWindowId,
+              const WorkerErrorReport& aReport, uint64_t aInnerWindowId,
               JS::Handle<JS::Value> aException = JS::NullHandleValue)
   {
     if (aWorkerPrivate) {
@@ -1092,16 +1085,16 @@ public:
 
     // We should not fire error events for warnings but instead make sure that
     // they show up in the error console.
-    if (!JSREPORT_IS_WARNING(aFlags)) {
+    if (!JSREPORT_IS_WARNING(aReport.mFlags)) {
       // First fire an ErrorEvent at the worker.
       RootedDictionary<ErrorEventInit> init(aCx);
 
-      if (aMutedError) {
+      if (aReport.mMutedError) {
         init.mMessage.AssignLiteral("Script error.");
       } else {
-        init.mMessage = aMessage;
-        init.mFilename = aFilename;
-        init.mLineno = aLineNumber;
+        init.mMessage = aReport.mMessage;
+        init.mFilename = aReport.mFilename;
+        init.mLineno = aReport.mLineNumber;
         init.mError = aException;
       }
 
@@ -1128,7 +1121,8 @@ public:
       // into an error event on our parent worker!
       // https://bugzilla.mozilla.org/show_bug.cgi?id=1271441 tracks making this
       // better.
-      if (aFireAtScope && (aTarget || aErrorNumber != JSMSG_OVER_RECURSED)) {
+      if (aFireAtScope &&
+          (aTarget || aReport.mErrorNumber != JSMSG_OVER_RECURSED)) {
         JS::Rooted<JSObject*> global(aCx, JS::CurrentGlobalOrNull(aCx));
         NS_ASSERTION(global, "This should never be null!");
 
@@ -1145,8 +1139,8 @@ public:
 
             MOZ_ASSERT_IF(globalScope, globalScope->GetWrapperPreserveColor() == global);
             if (globalScope || IsDebuggerSandbox(global)) {
-              aWorkerPrivate->ReportErrorToDebugger(aFilename, aLineNumber,
-                                                    aMessage);
+              aWorkerPrivate->ReportErrorToDebugger(aReport.mFilename, aReport.mLineNumber,
+                                                    aReport.mMessage);
               return;
             }
 
@@ -1193,28 +1187,20 @@ public:
     // Now fire a runnable to do the same on the parent's thread if we can.
     if (aWorkerPrivate) {
       RefPtr<ReportErrorRunnable> runnable =
-        new ReportErrorRunnable(aWorkerPrivate, aMessage, aFilename, aLine,
-                                aLineNumber, aColumnNumber, aFlags,
-                                aErrorNumber, aExnType, aMutedError);
+        new ReportErrorRunnable(aWorkerPrivate, aReport);
       runnable->Dispatch();
       return;
     }
 
     // Otherwise log an error to the error console.
-    LogErrorToConsole(aMessage, aFilename, aLine, aLineNumber, aColumnNumber,
-                      aFlags, aInnerWindowId);
+    LogErrorToConsole(aReport, aInnerWindowId);
   }
 
 private:
-  ReportErrorRunnable(WorkerPrivate* aWorkerPrivate, const nsString& aMessage,
-                      const nsString& aFilename, const nsString& aLine,
-                      uint32_t aLineNumber, uint32_t aColumnNumber,
-                      uint32_t aFlags, uint32_t aErrorNumber,
-                      JSExnType aExnType, bool aMutedError)
+  ReportErrorRunnable(WorkerPrivate* aWorkerPrivate,
+                      const WorkerErrorReport& aReport)
   : WorkerRunnable(aWorkerPrivate, ParentThreadUnchangedBusyCount),
-    mMessage(aMessage), mFilename(aFilename), mLine(aLine),
-    mLineNumber(aLineNumber), mColumnNumber(aColumnNumber), mFlags(aFlags),
-    mErrorNumber(aErrorNumber), mExnType(aExnType), mMutedError(aMutedError)
+    mReport(aReport)
   { }
 
   virtual void
@@ -1251,9 +1237,7 @@ private:
       }
 
       if (aWorkerPrivate->IsSharedWorker()) {
-        aWorkerPrivate->BroadcastErrorToSharedWorkers(aCx, mMessage, mFilename,
-                                                      mLine, mLineNumber,
-                                                      mColumnNumber, mFlags,
+        aWorkerPrivate->BroadcastErrorToSharedWorkers(aCx, &mReport,
                                                       /* isErrorEvent */ true);
         return true;
       }
@@ -1267,9 +1251,10 @@ private:
           swm->HandleError(aCx, aWorkerPrivate->GetPrincipal(),
                            aWorkerPrivate->WorkerName(),
                            aWorkerPrivate->ScriptURL(),
-                           mMessage,
-                           mFilename, mLine, mLineNumber,
-                           mColumnNumber, mFlags, mExnType);
+                           mReport.mMessage,
+                           mReport.mFilename, mReport.mLine, mReport.mLineNumber,
+                           mReport.mColumnNumber, mReport.mFlags,
+                           mReport.mExnType);
         }
         return true;
       }
@@ -1289,9 +1274,8 @@ private:
       return true;
     }
 
-    ReportError(aCx, parent, fireAtScope, aWorkerPrivate, mMessage,
-                mFilename, mLine, mLineNumber, mColumnNumber, mFlags,
-                mErrorNumber, mExnType, mMutedError, innerWindowId);
+    ReportError(aCx, parent, fireAtScope, aWorkerPrivate, mReport,
+                innerWindowId);
     return true;
   }
 };
@@ -3314,21 +3298,16 @@ template <class Derived>
 void
 WorkerPrivateParent<Derived>::BroadcastErrorToSharedWorkers(
                                                     JSContext* aCx,
-                                                    const nsAString& aMessage,
-                                                    const nsAString& aFilename,
-                                                    const nsAString& aLine,
-                                                    uint32_t aLineNumber,
-                                                    uint32_t aColumnNumber,
-                                                    uint32_t aFlags,
+                                                    const WorkerErrorReport* aReport,
                                                     bool aIsErrorEvent)
 {
   AssertIsOnMainThread();
 
-  if (JSREPORT_IS_WARNING(aFlags)) {
+  if (aIsErrorEvent && JSREPORT_IS_WARNING(aReport->mFlags)) {
     // Don't fire any events anywhere.  Just log to console.
     // XXXbz should we log to all the consoles of all the relevant windows?
-    LogErrorToConsole(aMessage, aFilename, aLine, aLineNumber, aColumnNumber,
-                      aFlags, 0);
+    MOZ_ASSERT(aReport);
+    LogErrorToConsole(*aReport, 0);
     return;
   }
 
@@ -3357,10 +3336,10 @@ WorkerPrivateParent<Derived>::BroadcastErrorToSharedWorkers(
       RootedDictionary<ErrorEventInit> errorInit(aCx);
       errorInit.mBubbles = false;
       errorInit.mCancelable = true;
-      errorInit.mMessage = aMessage;
-      errorInit.mFilename = aFilename;
-      errorInit.mLineno = aLineNumber;
-      errorInit.mColno = aColumnNumber;
+      errorInit.mMessage = aReport->mMessage;
+      errorInit.mFilename = aReport->mFilename;
+      errorInit.mLineno = aReport->mLineNumber;
+      errorInit.mColno = aReport->mColumnNumber;
 
       event = ErrorEvent::Constructor(sharedWorker, NS_LITERAL_STRING("error"),
                                       errorInit);
@@ -3426,9 +3405,9 @@ WorkerPrivateParent<Derived>::BroadcastErrorToSharedWorkers(
 
     MOZ_ASSERT(NS_IsMainThread());
     RootedDictionary<ErrorEventInit> init(aCx);
-    init.mLineno = aLineNumber;
-    init.mFilename = aFilename;
-    init.mMessage = aMessage;
+    init.mLineno = aReport->mLineNumber;
+    init.mFilename = aReport->mFilename;
+    init.mMessage = aReport->mMessage;
     init.mCancelable = true;
     init.mBubbles = true;
 
@@ -3446,8 +3425,8 @@ WorkerPrivateParent<Derived>::BroadcastErrorToSharedWorkers(
 
   // Finally log a warning in the console if no window tried to prevent it.
   if (shouldLogErrorToConsole) {
-    LogErrorToConsole(aMessage, aFilename, aLine, aLineNumber, aColumnNumber,
-                      aFlags, 0);
+    MOZ_ASSERT(aReport);
+    LogErrorToConsole(*aReport, 0);
   }
 }
 
@@ -4078,7 +4057,7 @@ WorkerDebugger::PostMessageToDebugger(const nsAString& aMessage)
 
   RefPtr<PostDebuggerMessageRunnable> runnable =
     new PostDebuggerMessageRunnable(this, aMessage);
-  if (NS_FAILED(mWorkerPrivate->DispatchToMainThread(runnable.forget()))) {
+  if (NS_FAILED(NS_DispatchToMainThread(runnable, NS_DISPATCH_NORMAL))) {
     NS_WARNING("Failed to post message to debugger on main thread!");
   }
 }
@@ -4103,7 +4082,7 @@ WorkerDebugger::ReportErrorToDebugger(const nsAString& aFilename,
 
   RefPtr<ReportDebuggerErrorRunnable> runnable =
     new ReportDebuggerErrorRunnable(this, aFilename, aLineno, aMessage);
-  if (NS_FAILED(mWorkerPrivate->DispatchToMainThread(runnable.forget()))) {
+  if (NS_FAILED(NS_DispatchToMainThread(runnable, NS_DISPATCH_NORMAL))) {
     NS_WARNING("Failed to report error to debugger on main thread!");
   }
 }
@@ -4120,7 +4099,10 @@ WorkerDebugger::ReportErrorToDebuggerOnMainThread(const nsAString& aFilename,
     listeners[index]->OnError(aFilename, aLineno, aMessage);
   }
 
-  LogErrorToConsole(aMessage, aFilename, nsString(), aLineno, 0, 0, 0);
+  WorkerErrorReport report;
+  report.mMessage = aMessage;
+  report.mFilename = aFilename;
+  LogErrorToConsole(report, 0);
 }
 
 WorkerPrivate::WorkerPrivate(WorkerPrivate* aParent,
@@ -4862,7 +4844,7 @@ WorkerPrivate::MaybeDispatchLoadFailedRunnable()
     return;
   }
 
-  MOZ_ALWAYS_SUCCEEDS(DispatchToMainThread(runnable.forget()));
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(runnable.forget()));
 }
 
 nsIEventTarget*
@@ -5083,7 +5065,7 @@ WorkerPrivate::ScheduleDeletion(WorkerRanOrNot aRanOrNot)
   else {
     RefPtr<TopLevelWorkerFinishedRunnable> runnable =
       new TopLevelWorkerFinishedRunnable(this);
-    if (NS_FAILED(DispatchToMainThread(runnable.forget()))) {
+    if (NS_FAILED(NS_DispatchToMainThread(runnable))) {
       NS_WARNING("Failed to dispatch runnable!");
     }
   }
@@ -5926,6 +5908,47 @@ WorkerPrivate::NotifyInternal(JSContext* aCx, Status aStatus)
 }
 
 void
+WorkerErrorBase::AssignErrorBase(JSErrorBase* aReport)
+{
+  mFilename = NS_ConvertUTF8toUTF16(aReport->filename);
+  mLineNumber = aReport->lineno;
+  mColumnNumber = aReport->column;
+  mErrorNumber = aReport->errorNumber;
+}
+
+void
+WorkerErrorNote::AssignErrorNote(JSErrorNotes::Note* aNote)
+{
+  WorkerErrorBase::AssignErrorBase(aNote);
+  xpc::ErrorNote::ErrorNoteToMessageString(aNote, mMessage);
+}
+
+void
+WorkerErrorReport::AssignErrorReport(JSErrorReport* aReport)
+{
+  WorkerErrorBase::AssignErrorBase(aReport);
+  xpc::ErrorReport::ErrorReportToMessageString(aReport, mMessage);
+
+  mLine.Assign(aReport->linebuf(), aReport->linebufLength());
+  mFlags = aReport->flags;
+  MOZ_ASSERT(aReport->exnType >= JSEXN_FIRST && aReport->exnType < JSEXN_LIMIT);
+  mExnType = JSExnType(aReport->exnType);
+  mMutedError = aReport->isMuted;
+
+  if (aReport->notes) {
+    if (!mNotes.SetLength(aReport->notes->length(), fallible)) {
+      return;
+    }
+
+    size_t i = 0;
+    for (auto&& note : *aReport->notes) {
+      mNotes.ElementAt(i).AssignErrorNote(note.get());
+      i++;
+    }
+  }
+}
+
+void
 WorkerPrivate::ReportError(JSContext* aCx, JS::ConstUTF8CharsZ aToStringResult,
                            JSErrorReport* aReport)
 {
@@ -5947,32 +5970,17 @@ WorkerPrivate::ReportError(JSContext* aCx, JS::ConstUTF8CharsZ aToStringResult,
   }
   JS_ClearPendingException(aCx);
 
-  nsString message, filename, line;
-  uint32_t lineNumber, columnNumber, flags, errorNumber;
-  JSExnType exnType = JSEXN_ERR;
-  bool mutedError = aReport && aReport->isMuted;
-
+  WorkerErrorReport report;
   if (aReport) {
-    // We want the same behavior here as xpc::ErrorReport::init here.
-    xpc::ErrorReport::ErrorReportToMessageString(aReport, message);
-
-    filename = NS_ConvertUTF8toUTF16(aReport->filename);
-    line.Assign(aReport->linebuf(), aReport->linebufLength());
-    lineNumber = aReport->lineno;
-    columnNumber = aReport->tokenOffset();
-    flags = aReport->flags;
-    errorNumber = aReport->errorNumber;
-    MOZ_ASSERT(aReport->exnType >= JSEXN_FIRST && aReport->exnType < JSEXN_LIMIT);
-    exnType = JSExnType(aReport->exnType);
+    report.AssignErrorReport(aReport);
   }
   else {
-    lineNumber = columnNumber = errorNumber = 0;
-    flags = nsIScriptError::errorFlag | nsIScriptError::exceptionFlag;
+    report.mFlags = nsIScriptError::errorFlag | nsIScriptError::exceptionFlag;
   }
 
-  if (message.IsEmpty() && aToStringResult) {
+  if (report.mMessage.IsEmpty() && aToStringResult) {
     nsDependentCString toStringResult(aToStringResult.c_str());
-    if (!AppendUTF8toUTF16(toStringResult, message, mozilla::fallible)) {
+    if (!AppendUTF8toUTF16(toStringResult, report.mMessage, mozilla::fallible)) {
       // Try again, with only a 1 KB string. Do this infallibly this time.
       // If the user doesn't have 1 KB to spare we're done anyways.
       uint32_t index = std::min(uint32_t(1024), toStringResult.Length());
@@ -5982,7 +5990,7 @@ WorkerPrivate::ReportError(JSContext* aCx, JS::ConstUTF8CharsZ aToStringResult,
 
       nsDependentCString truncatedToStringResult(aToStringResult.c_str(),
                                                  index);
-      AppendUTF8toUTF16(truncatedToStringResult, message);
+      AppendUTF8toUTF16(truncatedToStringResult, report.mMessage);
     }
   }
 
@@ -5991,13 +5999,11 @@ WorkerPrivate::ReportError(JSContext* aCx, JS::ConstUTF8CharsZ aToStringResult,
   // Don't want to run the scope's error handler if this is a recursive error or
   // if we ran out of memory.
   bool fireAtScope = mErrorHandlerRecursionCount == 1 &&
-                     errorNumber != JSMSG_OUT_OF_MEMORY &&
+                     report.mErrorNumber != JSMSG_OUT_OF_MEMORY &&
                      JS::CurrentGlobalOrNull(aCx);
 
-  ReportErrorRunnable::ReportError(aCx, this, fireAtScope, nullptr, message,
-                                   filename, line, lineNumber,
-                                   columnNumber, flags, errorNumber, exnType,
-                                   mutedError, 0, exn);
+  ReportErrorRunnable::ReportError(aCx, this, fireAtScope, nullptr, report, 0,
+                                   exn);
 
   mErrorHandlerRecursionCount--;
 }
diff --git a/dom/workers/WorkerPrivate.h b/dom/workers/WorkerPrivate.h
index 20a530205..885abccd5 100644
--- a/dom/workers/WorkerPrivate.h
+++ b/dom/workers/WorkerPrivate.h
@@ -140,6 +140,45 @@ public:
   }
 };
 
+class WorkerErrorBase {
+public:
+  nsString mMessage;
+  nsString mFilename;
+  uint32_t mLineNumber;
+  uint32_t mColumnNumber;
+  uint32_t mErrorNumber;
+
+  WorkerErrorBase()
+  : mLineNumber(0),
+    mColumnNumber(0),
+    mErrorNumber(0)
+  { }
+
+  void AssignErrorBase(JSErrorBase* aReport);
+};
+
+class WorkerErrorNote : public WorkerErrorBase {
+public:
+  void AssignErrorNote(JSErrorNotes::Note* aNote);
+};
+
+class WorkerErrorReport : public WorkerErrorBase {
+public:
+  nsString mLine;
+  uint32_t mFlags;
+  JSExnType mExnType;
+  bool mMutedError;
+  nsTArray<WorkerErrorNote> mNotes;
+
+  WorkerErrorReport()
+  : mFlags(0),
+    mExnType(JSEXN_ERR),
+    mMutedError(false)
+  { }
+
+  void AssignErrorReport(JSErrorReport* aReport);
+};
+
 template <class Derived>
 class WorkerPrivateParent : public DOMEventTargetHelper
 {
@@ -401,12 +440,7 @@ public:
 
   void
   BroadcastErrorToSharedWorkers(JSContext* aCx,
-                                const nsAString& aMessage,
-                                const nsAString& aFilename,
-                                const nsAString& aLine,
-                                uint32_t aLineNumber,
-                                uint32_t aColumnNumber,
-                                uint32_t aFlags,
+                                const WorkerErrorReport* aReport,
                                 bool aIsErrorEvent);
 
   void
diff --git a/dom/workers/WorkerRunnable.cpp b/dom/workers/WorkerRunnable.cpp
index 6bbe40f66..60d69d4e4 100644
--- a/dom/workers/WorkerRunnable.cpp
+++ b/dom/workers/WorkerRunnable.cpp
@@ -15,7 +15,6 @@
 #include "mozilla/DebugOnly.h"
 #include "mozilla/ErrorResult.h"
 #include "mozilla/dom/ScriptSettings.h"
-#include "mozilla/Telemetry.h"
 
 #include "js/RootingAPI.h"
 #include "js/Value.h"
@@ -118,7 +117,10 @@ WorkerRunnable::DispatchInternal()
     return NS_SUCCEEDED(parent->Dispatch(runnable.forget()));
   }
 
-  return NS_SUCCEEDED(mWorkerPrivate->DispatchToMainThread(runnable.forget()));
+  nsCOMPtr<nsIThread> mainThread = do_GetMainThread();
+  MOZ_ASSERT(mainThread);
+
+  return NS_SUCCEEDED(mainThread->Dispatch(runnable.forget(), NS_DISPATCH_NORMAL));
 }
 
 void
@@ -554,7 +556,10 @@ WorkerControlRunnable::DispatchInternal()
     return NS_SUCCEEDED(parent->DispatchControlRunnable(runnable.forget()));
   }
 
-  return NS_SUCCEEDED(mWorkerPrivate->DispatchToMainThread(runnable.forget()));
+  nsCOMPtr<nsIThread> mainThread = do_GetMainThread();
+  MOZ_ASSERT(mainThread);
+
+  return NS_SUCCEEDED(mainThread->Dispatch(runnable.forget(), NS_DISPATCH_NORMAL));
 }
 
 NS_IMPL_ISUPPORTS_INHERITED0(WorkerControlRunnable, WorkerRunnable)
@@ -572,8 +577,6 @@ WorkerMainThreadRunnable::Dispatch(Status aFailStatus, ErrorResult& aRv)
 {
   mWorkerPrivate->AssertIsOnWorkerThread();
 
-  TimeStamp startTime = TimeStamp::NowLoRes();
-
   AutoSyncLoopHolder syncLoop(mWorkerPrivate, aFailStatus);
 
   mSyncLoopTarget = syncLoop.GetEventTarget();
@@ -583,18 +586,16 @@ WorkerMainThreadRunnable::Dispatch(Status aFailStatus, ErrorResult& aRv)
     return;
   }
 
-  DebugOnly<nsresult> rv = mWorkerPrivate->DispatchToMainThread(this);
+  RefPtr<WorkerMainThreadRunnable> runnable(this);
+
+  DebugOnly<nsresult> rv =
+    NS_DispatchToMainThread(runnable.forget(), NS_DISPATCH_NORMAL);
   MOZ_ASSERT(NS_SUCCEEDED(rv),
              "Should only fail after xpcom-shutdown-threads and we're gone by then");
 
   if (!syncLoop.Run()) {
     aRv.ThrowUncatchableException();
   }
-
-  Telemetry::Accumulate(Telemetry::SYNC_WORKER_OPERATION, mTelemetryKey,
-                        static_cast<uint32_t>((TimeStamp::NowLoRes() - startTime)
-                                                .ToMilliseconds()));
-  Unused << startTime; // Shut the compiler up.
 }
 
 NS_IMETHODIMP
@@ -678,7 +679,7 @@ WorkerProxyToMainThreadRunnable::Dispatch()
     return false;
   }
 
-  if (NS_WARN_IF(NS_FAILED(mWorkerPrivate->DispatchToMainThread(this)))) {
+  if (NS_WARN_IF(NS_FAILED(NS_DispatchToMainThread(this)))) {
     ReleaseWorker();
     RunBackOnWorkerThread();
     return false;
diff --git a/dom/workers/WorkerScope.cpp b/dom/workers/WorkerScope.cpp
index 54252e53b..ace1a09fc 100644
--- a/dom/workers/WorkerScope.cpp
+++ b/dom/workers/WorkerScope.cpp
@@ -717,7 +717,7 @@ ServiceWorkerGlobalScope::SkipWaiting(ErrorResult& aRv)
     new WorkerScopeSkipWaitingRunnable(promiseProxy,
                                        NS_ConvertUTF16toUTF8(mScope));
 
-  MOZ_ALWAYS_SUCCEEDS(mWorkerPrivate->DispatchToMainThread(runnable.forget()));
+  MOZ_ALWAYS_SUCCEEDS(NS_DispatchToMainThread(runnable));
   return promise.forget();
 }
 
diff --git a/dom/workers/moz.build b/dom/workers/moz.build
index 4f4b52e4a..9fea84193 100644
--- a/dom/workers/moz.build
+++ b/dom/workers/moz.build
@@ -94,6 +94,7 @@ LOCAL_INCLUDES += [
     '../base',
     '../system',
     '/dom/base',
+    '/dom/bindings',
     '/xpcom/build',
     '/xpcom/threads',
 ]
diff --git a/dom/workers/test/test_sharedWorker.html b/dom/workers/test/test_sharedWorker.html
index 3d3d4e2c6..c00c4e586 100644
--- a/dom/workers/test/test_sharedWorker.html
+++ b/dom/workers/test/test_sharedWorker.html
@@ -23,7 +23,7 @@
         const errorFilename = href.substring(0, href.lastIndexOf("/") + 1) +
                               filename;
         const errorLine = 91;
-        const errorColumn = 0;
+        const errorColumn = 11;
 
         var worker = new SharedWorker(filename);