Integrate UI with authentication flow.

blimp/client/public/android/java/src/org/chromium/blimp_public/BlimpClientContextDelegate.java

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.blimp_public;
 
+import android.content.Context;
+
 /**
  * BlimpClientContextDelegate contains all embedder's Java functions used by Blimp Java classes.
  */
 public interface BlimpClientContextDelegate {
+    /**
+     * Request embedder to restart browser.
+     */
+    public void restartBrowser();
+
+    /**
+     * Start user sign in flow.
+     */
+    public void startUserSignInFlow(Context context);
 }