Bug 1425450 - Supress rooting analysis warning when removing a JS holder r=mccr8

Currently we get a rooting hazard when nsWrapperCache::UpdateWrapperForNewGlobal calls ReleaseWrapper because the analysis can't see through the virtual method call.

Differential Revision: https://phabricator.services.mozilla.com/D71600

xpcom/base/CycleCollectedJSRuntime.cpp

@@ -1293,6 +1293,9 @@ struct ClearJSHolder : public TraceCallbacks {
 void CycleCollectedJSRuntime::RemoveJSHolder(void* aHolder) {
   nsScriptObjectTracer* tracer = mJSHolders.GetAndRemove(aHolder);
   if (tracer) {
+    // Bug 1531951: The analysis can't see through the virtual call but we know
+    // that the ClearJSHolder tracer will never GC.
+    JS::AutoSuppressGCAnalysis nogc;
     tracer->Trace(aHolder, ClearJSHolder(), nullptr);
   }
 }