Bug 1644009 - P3. Revert "Bug 1592488 - P8. Ensure AbstractThread exists with STS thread." r=valentin,necko-reviewers

DirectTask dispatching will now be directly handled by nsThread.

Differential Revision: https://phabricator.services.mozilla.com/D79087

netwerk/base/nsSocketTransportService2.cpp

@@ -15,7 +15,6 @@
 #include "prerror.h"
 #include "nsServiceManagerUtils.h"
 #include "nsIObserverService.h"
-#include "mozilla/AbstractThread.h"
 #include "mozilla/Atomics.h"
 #include "mozilla/Services.h"
 #include "mozilla/Likely.h"
@@ -794,7 +793,6 @@ nsresult nsSocketTransportService::ShutdownThread() {
     MutexAutoLock lock(mLock);
     // Drop our reference to mThread and make sure that any concurrent
     // readers are excluded
-    mAbstractThread = nullptr;
     mThread = nullptr;
   }
 
@@ -1044,8 +1042,6 @@ nsSocketTransportService::Run() {
   }
 
   mRawThread = NS_GetCurrentThread();
-  mAbstractThread = AbstractThread::CreateXPCOMThreadWrapper(
-      mRawThread, false /* require taildispatch */);
 
   // hook ourselves up to observe event processing for this thread
   nsCOMPtr<nsIThreadInternal> threadInt = do_QueryInterface(mRawThread);

netwerk/base/nsSocketTransportService2.h

@@ -32,7 +32,6 @@ class nsIPrefBranch;
 //-----------------------------------------------------------------------------
 
 namespace mozilla {
-class AbstractThread;
 namespace net {
 
 //
@@ -144,10 +143,6 @@ class nsSocketTransportService final : public nsPISocketTransportService,
   //-------------------------------------------------------------------------
 
   nsCOMPtr<nsIThread> mThread;  // protected by mLock
-  // We create an AbstractThread for mThread thread so that we can use direct
-  // task dispatching with MozPromise, which is similar (but not identical to)
-  // the microtask semantics of JS promises.
-  RefPtr<AbstractThread> mAbstractThread;
   UniquePtr<PollableEvent> mPollableEvent;
 
   // Returns mThread, protecting the get-and-addref with mLock