Update demo with features from support lib 23.2.0

demos/src/main/java/org/chromium/customtabsdemos/CustomTabActivityHelper.java

 // Copyright 2015 Google Inc. All Rights Reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
 package org.chromium.customtabsdemos;
 
 import android.app.Activity;
-import android.content.ComponentName;
 import android.net.Uri;
 import android.os.Bundle;
-import android.support.annotation.NonNull;
 import android.support.customtabs.CustomTabsClient;
 import android.support.customtabs.CustomTabsIntent;
 import android.support.customtabs.CustomTabsServiceConnection;
 import android.support.customtabs.CustomTabsSession;
 
 import org.chromium.customtabsclient.shared.CustomTabsHelper;
 import org.chromium.customtabsclient.shared.ServiceConnection;
 import org.chromium.customtabsclient.shared.ServiceConnectionCallback;
 
-import java.lang.ref.WeakReference;
 import java.util.List;
 
 /**
  * This is a helper class to manage the connection to the Custom Tabs Service.
  */
 public class CustomTabActivityHelper implements ServiceConnectionCallback {
     private CustomTabsSession mCustomTabsSession;
     private CustomTabsClient mClient;
     private CustomTabsServiceConnection mConnection;
     private ConnectionCallback mConnectionCallback;
@@ skipping 121 matching lines @@
     public interface CustomTabFallback {
         /**
          *
          * @param activity The Activity that wants to open the Uri.
          * @param uri The uri to be opened by the fallback.
          */
         void openUri(Activity activity, Uri uri);
     }
 
 }