The EGL_CONFIG_ID attribute should be uniqueue for each config, at some cases we duplicate a configuration in order to simulate different pixel format (RGB_565) at that case we want to keep the native config_id of the backend OpenGL the same on both configs. This change adds extra attribute 'native_config_id' for that purpose. Change-Id: I7e560a4badd01d146b9753cee603ff4707ccfd7f