audioflinger: keep wakelock during offload drain am: de0613d0

    virtual     bool        waitingAsyncCallback_l();

    virtual     void        invalidateTracks(audio_stream_type_t streamType);

    virtual     bool        keepWakeLock() const { return mKeepWakeLock; }

    virtual     bool        keepWakeLock() const { return (mKeepWakeLock || (mDrainSequence & 1)); }

private:

    size_t      mPausedWriteLength;     // length in bytes of write interrupted by pause