Revert^2 "AudioFlinger: do not reset mHwPaused on flush"

This reverts commit 5f1ee2c965d5b15402f43c0c124e89d689bd7023.

Reason for revert: <The problem has been fixed at AOSP/2893100, this patch is ok to merge now>

Change-Id: I8431c6c0a368d986405c9200c55e24ff099c353d
diff --git a/services/audioflinger/Threads.cpp b/services/audioflinger/Threads.cpp
index bcd8b99..fd5d5fc 100644
--- a/services/audioflinger/Threads.cpp
+++ b/services/audioflinger/Threads.cpp
@@ -7145,11 +7145,14 @@
 {
     PlaybackThread::flushHw_l();
     mOutput->flush();
-    mHwPaused = false;
     mFlushPending = false;
     mTimestampVerifier.discontinuity(discontinuityForStandbyOrFlush());
     mTimestamp.clear();
     mMonotonicFrameCounter.onFlush();
+    // We do not reset mHwPaused which is hidden from the Track client.
+    // Note: the client track in Tracks.cpp and AudioTrack.cpp
+    // has a FLUSHED state but the DirectOutputThread does not;
+    // those tracks will continue to show isStopped().
 }
 
 int64_t DirectOutputThread::computeWaitTimeNs_l() const {