Stop the endpoint synchronously in RTCPeerConnection::close

https://bugs.webkit.org/show_bug.cgi?id=194688

Reviewed by Eric Carlson.

In the case where the peer connection is being closed, it was asynchronously stopping the endpoint.
But the endpoint, before being stopped, could try to fire an event.
If the context is gone in between, we end up with a null pointer dereference.

* Modules/mediastream/RTCPeerConnection.cpp:
(WebCore::RTCPeerConnection::close):


Canonical link: https://commits.webkit.org/209090@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@241592 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebCore/ChangeLog

@@ -1,3 +1,17 @@
+2019-02-15  Youenn Fablet  <youenn@apple.com>
+
+        Stop the endpoint synchronously in RTCPeerConnection::close
+        https://bugs.webkit.org/show_bug.cgi?id=194688
+
+        Reviewed by Eric Carlson.
+
+        In the case where the peer connection is being closed, it was asynchronously stopping the endpoint.
+        But the endpoint, before being stopped, could try to fire an event.
+        If the context is gone in between, we end up with a null pointer dereference.
+
+        * Modules/mediastream/RTCPeerConnection.cpp:
+        (WebCore::RTCPeerConnection::close):
+
 2019-02-15  Zalan Bujtas  <zalan@apple.com>
 
         [LFC] Out-of-flow box is never a float box

Source/WebCore/Modules/mediastream/RTCPeerConnection.cpp

@@ -437,9 +437,7 @@ void RTCPeerConnection::close()
 
     updateConnectionState();
     ASSERT(isClosed());
-    scriptExecutionContext()->postTask([protectedThis = makeRef(*this)](ScriptExecutionContext&) {
-        protectedThis->doStop();
-    });
+    doStop();
 }
 
 void RTCPeerConnection::emulatePlatformEvent(const String& action)