Move //webapk to //chrome/android/webapk

chrome/android/webapk/shell_apk/javatests/dex_optimizer/AndroidManifest.xml

 <?xml version="1.0" encoding="utf-8"?>
 <!-- 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.
 -->
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="org.chromium.webapk.shell_apk.test.dex_optimizer"
     android:versionName="1.0" >
 
     <uses-sdk
         android:minSdkVersion="16"
         android:targetSdkVersion="23" />
 
     <application android:label="DexOptimizer">
         <service
             android:name="org.chromium.webapk.shell_apk.test.dex_optimizer.DexOptimizerServiceImpl"
             android:exported="true">
         </service>
     </application>
 
 </manifest>