Revert "Revert "[BR07.1] Expose setDataSaverEnabled from Connect..."

Revert submission 2799494-revert-2745215-npmsbpf-OBOPDXREUI

Reason for revert: Need to 1. Merge API first. 2. Wait for prebuilt. 3. Merge the caller.

Reverted changes: /q/submissionid:2799494-revert-2745215-npmsbpf-OBOPDXREUI

Change-Id: Icd5f3d40595a0d2a221b016cec70568bf3597c16
diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index c19878c..967bcc8 100755
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -12545,6 +12545,20 @@
     }
 
     @Override
+    public void setDataSaverEnabled(final boolean enable) {
+        enforceNetworkStackOrSettingsPermission();
+        try {
+            final boolean ret = mNetd.bandwidthEnableDataSaver(enable);
+            if (!ret) {
+                throw new IllegalStateException("Error when changing iptables: " + enable);
+            }
+        } catch (RemoteException e) {
+            // Lack of permission or binder errors.
+            throw new IllegalStateException(e);
+        }
+    }
+
+    @Override
     public void updateMeteredNetworkAllowList(final int uid, final boolean add) {
         enforceNetworkStackOrSettingsPermission();