Revert "Workaround slow AudioTrack destruction"

    mSoundPool = soundPool;

}

// This class is used to destroy a RefBase asynchronously

class AsyncDestructThread : public Thread

{

public:

    AsyncDestructThread(sp<RefBase> refBase) : mRefBase(refBase) { }

protected:

    virtual ~AsyncDestructThread() { }

private:

    virtual bool        threadLoop()    { return false; }

    const   sp<RefBase> mRefBase;

};

// call with sound pool lock held

void SoundChannel::play(const sp<Sample>& sample, int nextChannelID, float leftVolume,

        float rightVolume, int priority, int loop, float rate)

    if (status != NO_ERROR) {

        mAudioTrack.clear();

    }

    // FIXME AudioTrack destruction should not be slow

    if (oldTrack != 0) {

        // must be a raw reference to avoid a race after run()

        AsyncDestructThread *adt = new AsyncDestructThread(oldTrack);

        // guaranteed to not run destructor

        oldTrack.clear();

        // after the run(), adt thread will hold a strong reference to oldTrack,

        // and the only strong reference to itself

        adt->run("AsyncDestruct");

        // do not delete adt here: adt thread destroys itself, and oldTrack if needed

    }

}

void SoundChannel::nextEvent()