Bug 1349699 - Assert when destroying a MessageLoop that a live MessageChannel is attached to (r=dvander)

MozReview-Commit-ID: GGr5UqJl3ui

ipc/glue/MessageChannel.cpp

@@ -488,8 +488,10 @@ private:
     nsAutoPtr<IPC::Message> mReply;
 };
 
-MessageChannel::MessageChannel(IToplevelProtocol *aListener)
-  : mListener(aListener),
+MessageChannel::MessageChannel(const char* aName,
+                               IToplevelProtocol *aListener)
+  : mName(aName),
+    mListener(aListener),
     mChannelState(ChannelClosed),
     mSide(UnknownSide),
     mLink(nullptr),
@@ -627,6 +629,18 @@ MessageChannel::CanSend() const
     return Connected();
 }
 
+void
+MessageChannel::WillDestroyCurrentMessageLoop()
+{
+#if !defined(ANDROID)
+#if defined(MOZ_CRASHREPORTER)
+    CrashReporter::AnnotateCrashReport(NS_LITERAL_CSTRING("ProtocolName"),
+                                       nsDependentCString(mName));
+#endif
+    MOZ_CRASH("MessageLoop destroyed before MessageChannel that's bound to it");
+#endif
+}
+
 void
 MessageChannel::Clear()
 {
@@ -644,6 +658,10 @@ MessageChannel::Clear()
         gParentProcessBlocker = nullptr;
     }
 
+    if (mWorkerLoop) {
+        mWorkerLoop->RemoveDestructionObserver(this);
+    }
+
     mWorkerLoop = nullptr;
     delete mLink;
     mLink = nullptr;
@@ -676,6 +694,8 @@ MessageChannel::Open(Transport* aTransport, MessageLoop* aIOLoop, Side aSide)
     mWorkerLoop = MessageLoop::current();
     mWorkerLoopID = mWorkerLoop->id();
 
+    mWorkerLoop->AddDestructionObserver(this);
+
     ProcessLink *link = new ProcessLink(this);
     link->Open(aTransport, aIOLoop, aSide); // :TODO: n.b.: sets mChild
     mLink = link;
@@ -752,6 +772,7 @@ MessageChannel::CommonThreadOpenInit(MessageChannel *aTargetChan, Side aSide)
 {
     mWorkerLoop = MessageLoop::current();
     mWorkerLoopID = mWorkerLoop->id();
+    mWorkerLoop->AddDestructionObserver(this);
     mLink = new ThreadLink(this, aTargetChan);
     mSide = aSide;
 }