Migrated VmsClientStats puller to new API

CarStatsService registers the VmsClientStats puller with
StatsManager using a new API exposed as part of statsd's mainline
efforts. This migration makes the pullData service obsolete, so
CarStatsService no longer implements ICarStatsService. Additionally, the
dependency on StatsLogEventWrapper is removed.

This CL partially reverts changes made in ag/9687258.

Test: m -j CarService
Test: stats_testdrive 10065
Bug: 148123503
Change-Id: I63128d101a11d5354b43e4f7b1643b92837b5f7a
diff --git a/service/src/com/android/car/ICarImpl.java b/service/src/com/android/car/ICarImpl.java
index bcdc640..257e960 100644
--- a/service/src/com/android/car/ICarImpl.java
+++ b/service/src/com/android/car/ICarImpl.java
@@ -204,6 +204,7 @@
         mSystemStateControllerService = new SystemStateControllerService(
                 serviceContext, mCarAudioService, this);
         mCarStatsService = new CarStatsService(serviceContext);
+        mCarStatsService.init();
         if (mFeatureController.isFeatureEnabled(Car.VMS_SUBSCRIBER_SERVICE)) {
             mVmsBrokerService = new VmsBrokerService();
             mVmsClientManager = new VmsClientManager(
@@ -518,10 +519,6 @@
         }
     }
 
-    CarStatsService getStatsService() {
-        return mCarStatsService;
-    }
-
     public static void assertVehicleHalMockPermission(Context context) {
         assertPermission(context, Car.PERMISSION_MOCK_VEHICLE_HAL);
     }