void cancel() {
        status = Status.CANCELLED;
        if (loadStatus != null) {
            loadStatus.cancel();
            loadStatus = null;
        }
    }
Cancels the current load but does not release any resources held by the request and continues to display
the loaded resource if the load completed before the call to cancel.

<p>
    Cancelled requests can be restarted with a subsequent call to {@link #begin()}.
</p>

@see #clear()
core/src/main/java/com/bumptech/glide/request/GenericRequest.java