title: What does the RC_SIGN_IN means in googleplus login
body: <p>I need to add login with google plus button to my app. I followed google's documentation in this <a href="https://developers.google.com/identity/sign-in/android/sign-in" rel="noreferrer">Link</a>. But in signin method there is a value called <code>RC_SIGN_IN</code>. I do not know what are the values I should assign to <code>RC_SIGN_IN</code>.</p>