Merge "aaudio: warn if a callback stream is written to" into sc-dev

    // Don't allow writes when playing with a callback.

    if (audioStream->isDataCallbackActive()) {

        ALOGD("Cannot write to a callback stream when running.");

        // A developer requested this warning because it would have saved lots of debugging.

        ALOGW("%s() - Cannot write to a callback stream when running.", __func__);

        return AAUDIO_ERROR_INVALID_STATE;

    }