Refactor WebApkServiceConnectionManager.

chrome/android/webapk/shell_apk/AndroidManifest.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.
 -->
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     package="{{{manifest_package}}}"
     android:versionCode="{{{version_code}}}"
     android:versionName="{{{version_name}}}" >
@@ skipping 53 matching lines @@
         <service android:name="org.chromium.webapk.shell_apk.WebApkSandboxedProcessService1"
             android:isolatedProcess="true"
             android:process=":webapk_sandboxed_process1"
             android:exported="true"
             tools:ignore="ExportedService"/>
         <service android:name="org.chromium.webapk.shell_apk.WebApkSandboxedProcessService2"
             android:isolatedProcess="true"
             android:process=":webapk_sandboxed_process2"
             android:exported="true"
             tools:ignore="ExportedService"/>
+        <service
+            android:name="org.chromium.webapk.shell_apk.IdentityService"
+            android:exported="true"
+            tools:ignore="ExportedService">
+            <intent-filter>
+              <action android:name="org.webapk.IDENTITY_SERVICE_API" />
+            </intent-filter>
+        </service>
     </application>
 </manifest>