protected Headers getHeaders(T model, int width, int height) {
        return Headers.DEFAULT;
    }
Get the headers for the given model and dimensions as a map of strings to sets of strings.

@param model The model.
@param width The width in pixels of the view/target the image will be loaded into.
@param height The height in pixels of the view/target the image will be loaded into.
@return The Headers object containing the headers, or null if no headers should be added.
core/src/main/java/com/bumptech/glide/load/model/stream/BaseGlideUrlLoader.java