[BR14] Tracker Data Saver status in ConnectivityService

BYPASS_INCLUSIVE_LANGUAGE_REASON=Using public API
Test: atest ConnectivityCoverageTests:android.net.connectivity.com.android.server.CSBpfNetMapsTest
      (on U and V devices respectively)
Bug: 297836825
Fix: 314858283

Change-Id: Ibeac8cd3a33468c6539234255328affc6b3f8ffe