idl: synchronizationsource is a *unsigned* long

Author: fippo

index.bs

@@ -292,9 +292,9 @@ dictionary RTCEncodedVideoFrameMetadata {
     unsigned short height;
     long spatialIndex;
     long temporalIndex;
-    long synchronizationSource;
+    unsigned long synchronizationSource;
     octet payloadType;
-    sequence<long> contributingSources;
+    sequence<unsigned long> contributingSources;
 };
 
 // New interfaces to define encoded video and audio frames. Will eventually
@@ -308,9 +308,9 @@ interface RTCEncodedVideoFrame {
 };
 
 dictionary RTCEncodedAudioFrameMetadata {
-    long synchronizationSource;
+    unsigned long synchronizationSource;
     octet payloadType;
-    sequence<long> contributingSources;
+    sequence<unsigned long> contributingSources;
 };
 
 [Exposed=(Window,DedicatedWorker)]