Initial implementation of the Auto-Fill Framework classes.

This CL provides the initial, skeleton implementation of the Auto-Fill
Framework classes:

- Defines the system service and app-based
  AIDL (IAutoFillManagerService.aidl and IAutoFillService.aidl respectively).
- Defines the 'adb shell cmd' interface.
- Defines the permission required to access the service.
- Registers the service on SystemServer.
- Adds the code to bind the app-specified service to system_server.
- Defines the service class (AutoFillService) required by providers.
- Implements the initial startSession() method.

This is still a very early, "work-in-progress" change:
- It has many TODOs.
- It does not have unit or CTS tests yet.
- It does not provide a callback method to auto-fill the fields.
- In fact, it has a lot of TODOs.

Despite these adversities, it can be tested by following the steps
below:

1.Create an app with a service extending AutoFillService

2.Implement the onNewSession() method

3.In the manifest:
 - Listen to android.service.autofill.AutoFillService intents.
 - Require the android.permission.BIND_AUTO_FILL permission.

4.Explicitly set the app as an autofill-service by running:
  adb shell settings put secure auto_fill_service MY_APP/.MY_SERVICE

5.Start a session against the top activity:
  adb shell cmd autofill start session

BUG: 31001899
Test: manually built and ran it

Change-Id: I00f4822159b31ddddba8f513e57c4474bc74eb89
diff --git a/services/java/com/android/server/SystemServer.java b/services/java/com/android/server/SystemServer.java
index cc96f56..211e3b8 100644
--- a/services/java/com/android/server/SystemServer.java
+++ b/services/java/com/android/server/SystemServer.java
@@ -184,6 +184,8 @@
             "com.android.server.content.ContentService$Lifecycle";
     private static final String WALLPAPER_SERVICE_CLASS =
             "com.android.server.wallpaper.WallpaperManagerService$Lifecycle";
+    private static final String AUTO_FILL_MANAGER_SERVICE_CLASS =
+            "com.android.server.autofill.AutoFillManagerService";
 
     private static final String PERSISTENT_DATA_BLOCK_PROP = "ro.frp.pst";
 
@@ -1362,6 +1364,10 @@
         mSystemServiceManager.startService(RetailDemoModeService.class);
         traceEnd();
 
+        traceBeginAndSlog("StartAutoFillService");
+        mSystemServiceManager.startService(AUTO_FILL_MANAGER_SERVICE_CLASS);
+        traceEnd();
+
         // It is now time to start up the app processes...
 
         traceBeginAndSlog("MakeVibratorServiceReady");