Revert "AudioFlinger: Keep track of music effect thread when pri..."

Revert submission 25712917

Reason for revert: Droid-monitor triggered revert likely due to breakage in b/330202134. Will be verifying through ABTD before submission.

Reverted changes: /q/submissionid:25712917

Change-Id: Iacde14e4dc8c644b55741557bce81101ce2b5f19
diff --git a/services/audioflinger/Effects.h b/services/audioflinger/Effects.h
index 5e527d3..46c44a6 100644
--- a/services/audioflinger/Effects.h
+++ b/services/audioflinger/Effects.h
@@ -616,9 +616,7 @@
             mThreadType = thread->type();
             mAfThreadCallback = thread->afThreadCallback();
         }
-        bool hasThreadAttached() const {
-            return thread().promote() != nullptr;
-        }
+
     private:
         const wp<IAfEffectChain> mChain;
         mediautils::atomic_wp<IAfThreadBase> mThread;