[Android]: Hide add-to-homescreen app menu item when WebAPK is installed

chrome/android/java/res/menu/custom_tabs_menu.xml

 <?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright 2015 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. -->
 
 <menu xmlns:android="http://schemas.android.com/apk/res/android">
         <item android:id="@+id/icon_row_menu_id"
             android:title="@null"
             android:orderInCategory="0" >
             <menu>
@@ skipping 24 matching lines @@
                 android:title="@null" />
           </menu>
         </item>
         <!-- Title is intentionally left blank in xml and will be set in java. -->
         <item android:id="@+id/find_in_page_id"
             android:title="@string/menu_find_in_page"
             android:orderInCategory="2" />
         <item android:id="@+id/add_to_homescreen_id"
             android:title="@string/menu_add_to_homescreen"
             android:orderInCategory="2" />
+        <item android:id="@+id/open_webapk_id"
+            android:title="@string/menu_open_webapk"
+            android:orderInCategory="2" />
         <item android:id="@+id/request_desktop_site_id"
             android:title="@string/menu_request_desktop_site"
             android:checkable="true"
             android:icon="?android:attr/listChoiceIndicatorMultiple"
             android:orderInCategory="2" />
         <item android:id="@+id/open_in_browser_id"
             android:title=""
             android:orderInCategory="2" />
-</menu>
+</menu>