Bug 1617437 - TaskQueue.h: Fix a -Wnon-c-typedef-for-linkage warning r=froydnj

Depends on D63781

Differential Revision: https://phabricator.services.mozilla.com/D63783

--HG--
extra : moz-landing-system : lando

Author: sylvestre

xpcom/threads/TaskQueue.h

@@ -128,7 +128,7 @@ class TaskQueue : public AbstractThread {
   // Monitor that protects the queue and mIsRunning;
   Monitor mQueueMonitor;
 
-  typedef struct {
+  typedef struct TaskStruct {
     nsCOMPtr<nsIRunnable> event;
     uint32_t flags;
   } TaskStruct;