Don't remove effects on session 0

b/5159902
Change-Id: Id6f29fb1c687069f7480dd81d4745a558f202226
diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
index 95c469d..941c9c8 100644
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -5118,7 +5118,9 @@
         sp<PlaybackThread> t = mPlaybackThreads.valueAt(i);
         for (size_t j = 0; j < t->mEffectChains.size(); j++) {
             sp<EffectChain> ec = t->mEffectChains[j];
-            chains.push(ec);
+            if (ec->sessionId() > AUDIO_SESSION_OUTPUT_MIX) {
+                chains.push(ec);
+            }
         }
     }
     for (size_t i = 0; i < mRecordThreads.size(); i++) {