Fixed problems in audio effect volume control.

Fixed the following problems in audio effect volume control in AudioFlinger:
- Make sure that the volumes returned by EffectChain::setVolume_l() are correct even is
no change is detected since last call
- Do not use isEnabled() to validate volume control but mState >= ACTIVE instead as the volume control
must be also active in STOPPING and STOPPED states.

Change-Id: Id62da3164fad500ee8a5efd6cd78c77e8fdcb541
diff --git a/services/audioflinger/AudioFlinger.h b/services/audioflinger/AudioFlinger.h
index 4507a48..99816f9 100644
--- a/services/audioflinger/AudioFlinger.h
+++ b/services/audioflinger/AudioFlinger.h
@@ -1110,6 +1110,9 @@
         int mVolumeCtrlIdx;         // index of insert effect having control over volume
         uint32_t mLeftVolume;       // previous volume on left channel
         uint32_t mRightVolume;      // previous volume on right channel
+        uint32_t mNewLeftVolume;       // new volume on left channel
+        uint32_t mNewRightVolume;      // new volume on right channel
+
     };
 
     friend class RecordThread;