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/Android.mk b/Android.mk
index 7c9397f..6180667 100644
--- a/Android.mk
+++ b/Android.mk
@@ -305,6 +305,7 @@
 	core/java/android/service/wallpaper/IWallpaperService.aidl \
 	core/java/android/service/chooser/IChooserTargetService.aidl \
 	core/java/android/service/chooser/IChooserTargetResult.aidl \
+	core/java/android/text/ITextClassificationService.aidl \
 	core/java/android/view/accessibility/IAccessibilityInteractionConnection.aidl\
 	core/java/android/view/accessibility/IAccessibilityInteractionConnectionCallback.aidl\
 	core/java/android/view/accessibility/IAccessibilityManager.aidl \