Implement TextClassification system service.

- This service provides the TextClassificationManager access to the
  classification model file.
  See: Icb82b707c9c1b4dcb739f44d888bbc43bc3b03bb
- This service is started at boot time.
  See: Ie4a597bc5c6c4140afbcf7feaa9dd237a3fd5fef

Test: Manually tested. Also see: Ic2a5eceeaec4cd2943c6c753084df46d30511fee
Bug: 32503402
Change-Id: Ic428d00f291e268211866b3fc6b7acbc3eb04e1e
diff --git a/services/java/com/android/server/SystemServer.java b/services/java/com/android/server/SystemServer.java
index 1d550d2..5719564 100644
--- a/services/java/com/android/server/SystemServer.java
+++ b/services/java/com/android/server/SystemServer.java
@@ -100,6 +100,7 @@
 import com.android.server.statusbar.StatusBarManagerService;
 import com.android.server.storage.DeviceStorageMonitorService;
 import com.android.server.telecom.TelecomLoaderService;
+import com.android.server.text.TextClassificationService;
 import com.android.server.trust.TrustManagerService;
 import com.android.server.tv.TvInputManagerService;
 import com.android.server.tv.TvRemoteService;
@@ -896,6 +897,12 @@
                 traceEnd();
             }
 
+            if (!disableNonCoreServices) {
+                traceBeginAndSlog("StartTextClassificationService");
+                mSystemServiceManager.startService(TextClassificationService.Lifecycle.class);
+                traceEnd();
+            }
+
             if (!disableNetwork) {
                 traceBeginAndSlog("StartNetworkScoreService");
                 try {