title: android can not add accessibility on 4.2
body: <p>I have written my own accessibility service. It works fine on 4.1.1 and below. However, I found out that I couldn't find the service on 4.2.2 in Settings>Accessibility. Is there something I should know about accessibily on 4.2.2?</p>
  
  <p>this is I declare in Android Manifest</p>
  
  <pre><code>&lt;service android:name="my_service_name"
                      android:label="@string/accessibility_service_lable"&gt;
                          &lt;meta-data 
                              android:name="android.accessibilityservice"
                              android:resource="@xml/accessibility_service_config"/&gt;
                      &lt;intent-filter &gt;
                          &lt;action android:name="android.accessibilityservice.AccessibilityService"/&gt;
                      &lt;/intent-filter&gt;
                  &lt;/service&gt;
  &lt;uses-permission android:name="android.permission.BIND_ACCESSIBILITY_SERVICE" /&gt;
  </code></pre>
  
  <p>the follow is the config file, it is very simple.</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;accessibility-service xmlns:android="http://schemas.android.com/apk/res/android"
      android:description="@string/accessibility_service_description"
      /&gt;
  </code></pre>