Add slide in/slide out transition for Herb CCTs

chrome/android/java/src/org/chromium/chrome/browser/customtabs/SeparateTaskCustomTabActivity.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.chrome.browser.customtabs;
 
 import android.content.Intent;
 import android.os.Build;
 
 import org.chromium.base.ApiCompatibilityUtils;
@@ skipping 50 matching lines @@
 
     @Override
     public void finishAndClose() {
         if (mDidFinishForReparenting) return;
 
         mDidFinishForReparenting = true;
         if (getCallingActivity() != null) {
             finish();
         } else if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
             ApiCompatibilityUtils.finishAndRemoveTask(this);
+
+            if (getIntentDataProvider() != null && getIntentDataProvider().isOpenedByChrome()) {
+                overridePendingTransition(R.anim.no_anim, R.anim.slide_out_down);
+            }
         } else {
             // TODO(tedchoc): This does not work reliably :-/.  Need to find a solution for the X
             //                button and the Android back.  Seems to only somewhat work for the
             //                open in Chrome case.
             Intent intent = new Intent(getIntent());
             intent.addFlags(Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);
             startActivity(intent);
             overridePendingTransition(0, 0);
         }
     }
 }