From 1a479b5239ed9b51d7513c291283406545cfff19 Mon Sep 17 00:00:00 2001
From: Brian Hackett <bhackett1024@gmail.com>
Date: Mon, 23 Jul 2018 14:58:20 +0000
Subject: [PATCH] Bug 1465294 Part 16 - Support web workers when
 recording/replaying, r=smaug.

---
 dom/workers/RuntimeService.cpp | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/dom/workers/RuntimeService.cpp b/dom/workers/RuntimeService.cpp
index 789bfa59f5bc..ba9d18bc448c 100644
--- a/dom/workers/RuntimeService.cpp
+++ b/dom/workers/RuntimeService.cpp
@@ -576,6 +576,13 @@ InterruptCallback(JSContext* aCx)
   WorkerPrivate* worker = GetWorkerPrivateFromContext(aCx);
   MOZ_ASSERT(worker);
 
+  // As with the main thread, the interrupt callback is triggered
+  // non-deterministically when recording/replaying, so return early to avoid
+  // performing any recorded events.
+  if (recordreplay::IsRecordingOrReplaying()) {
+    return true;
+  }
+
   // Now is a good time to turn on profiling if it's pending.
   PROFILER_JS_INTERRUPT_CALLBACK();
 
@@ -965,6 +972,11 @@ public:
         NS_WARNING("failed to set workerCx's default locale");
       }
     }
+
+    // Cycle collections must occur at consistent points when recording/replaying.
+    if (recordreplay::IsRecordingOrReplaying()) {
+      recordreplay::RegisterTrigger(this, [=]() { nsCycleCollector_collect(nullptr); });
+    }
   }
 
   void Shutdown(JSContext* cx) override
@@ -979,6 +991,10 @@ public:
   ~WorkerJSRuntime()
   {
     MOZ_COUNT_DTOR_INHERITED(WorkerJSRuntime, CycleCollectedJSRuntime);
+
+    if (recordreplay::IsRecordingOrReplaying()) {
+      recordreplay::UnregisterTrigger(this);
+    }
   }
 
   virtual void
@@ -1015,7 +1031,11 @@ public:
     mWorkerPrivate->AssertIsOnWorkerThread();
 
     if (aStatus == JSGC_END) {
-      nsCycleCollector_collect(nullptr);
+      if (recordreplay::IsRecordingOrReplaying()) {
+        recordreplay::ActivateTrigger(this);
+      } else {
+        nsCycleCollector_collect(nullptr);
+      }
     }
   }