PayPalOneTouch/src/main/java/com/paypal/android/sdk/onetouch/core/Request.java
@SuppressWarnings("unchecked")
    public T successUrl(String scheme, String host) {
        mSuccessUrl = scheme + "://" + redirectURLHostAndPath() + host;
        return (T) this;
    }
@SuppressWarnings("unchecked")
    public T successUrl(String scheme, String host) {
        mSuccessUrl = scheme + "://" + redirectURLHostAndPath() + host;
        return (T) this;
    }
Defines the host to be used in the success url for browser switch (the package name will be
used as the scheme)