Revert "Add feature flag for "no data" backup calls"

This reverts commit 27c64a3bed.

Reason for revert: The GMSCore code to handle the flag will be part of DP2 and so we can remove the flag ahead of the cut.

GMSCore CL Status; https://cl-status.corp.google.com/#/summary/gmscore_prod/291378558
GMSCore Calendar; http://go/gms-schedule

Bug: 147481066
Test: m -j RunBackupFrameworksServicesRoboTests
Change-Id: I4159e064e739c6f366063c7fadd7cca40a7f07d9

core/java/android/util/FeatureFlagUtils.java

@@ -45,9 +45,6 @@ public class FeatureFlagUtils {
     public static final String NOTIF_CONVO_BYPASS_SHORTCUT_REQ =
             "settings_notif_convo_bypass_shortcut_req";
     /** @hide */
-    public static final String BACKUP_NO_KV_DATA_CHANGE_CALLS =
-            "backup_enable_no_data_notification_calls";
-    /** @hide */
     public static final String SETTINGS_DO_NOT_RESTORE_PRESERVED =
             "settings_do_not_restore_preserved";
     /** @hide */
@@ -70,9 +67,6 @@ public class FeatureFlagUtils {
         DEFAULT_FLAGS.put("settings_controller_loading_enhancement", "false");
         DEFAULT_FLAGS.put("settings_conditionals", "false");
         DEFAULT_FLAGS.put(NOTIF_CONVO_BYPASS_SHORTCUT_REQ, "true");
-
-        // Disabled until backup transports support it.
-        DEFAULT_FLAGS.put(BACKUP_NO_KV_DATA_CHANGE_CALLS, "false");
         // Disabled by default until b/148278926 is resolved. This flags guards a feature
         // introduced in R and will be removed in the next release (b/148367230).
         DEFAULT_FLAGS.put(SETTINGS_DO_NOT_RESTORE_PRESERVED, "false");

services/backup/java/com/android/server/backup/keyvalue/KeyValueBackupTask.java

@@ -47,7 +47,6 @@ import android.os.RemoteException;
 import android.os.SELinux;
 import android.os.UserHandle;
 import android.os.WorkSource;
-import android.util.FeatureFlagUtils;
 import android.util.Log;
 
 import com.android.internal.annotations.GuardedBy;
@@ -400,12 +399,6 @@ public class KeyValueBackupTask implements BackupRestoreTask, Runnable {
      *                     the transport have no data.
      */
     private void informTransportOfUnchangedApps(Set<String> appsBackedUp) {
-        // If the feautre is not enabled then we just exit early.
-        if (!FeatureFlagUtils.isEnabled(mBackupManagerService.getContext(),
-                FeatureFlagUtils.BACKUP_NO_KV_DATA_CHANGE_CALLS)) {
-            return;
-        }
-
         String[] succeedingPackages = getSucceedingPackages();
         if (succeedingPackages == null) {
             // Nothing is succeeding, so end early.

services/robotests/backup/src/com/android/server/backup/keyvalue/KeyValueBackupTaskTest.java

@@ -96,7 +96,6 @@ import android.os.Message;
 import android.os.ParcelFileDescriptor;
 import android.os.RemoteException;
 import android.platform.test.annotations.Presubmit;
-import android.util.FeatureFlagUtils;
 import android.util.Pair;
 
 import com.android.internal.backup.IBackupTransport;
@@ -259,9 +258,6 @@ public class KeyValueBackupTaskTest  {
     public void tearDown() throws Exception {
         ShadowBackupDataInput.reset();
         ShadowApplicationPackageManager.reset();
-        // False by default.
-        FeatureFlagUtils.setEnabled(
-                mContext, FeatureFlagUtils.BACKUP_NO_KV_DATA_CHANGE_CALLS, false);
     }
 
     @Test
@@ -2348,9 +2344,6 @@ public class KeyValueBackupTaskTest  {
     @Test
     public void testRunTask_whenNoDataToBackupOnFirstBackup_doesNotTellTransportOfBackup()
             throws Exception {
-        FeatureFlagUtils.setEnabled(
-                mContext, FeatureFlagUtils.BACKUP_NO_KV_DATA_CHANGE_CALLS, true);
-
         TransportMock transportMock = setUpInitializedTransport(mTransport);
         mBackupManagerService.setCurrentToken(0L);
         when(transportMock.transport.getCurrentRestoreSet()).thenReturn(1234L);
@@ -2368,9 +2361,6 @@ public class KeyValueBackupTaskTest  {
     @Test
     public void testRunTask_whenBackupHasCompletedAndThenNoDataChanges_transportGetsNotified()
             throws Exception {
-        FeatureFlagUtils.setEnabled(
-                mContext, FeatureFlagUtils.BACKUP_NO_KV_DATA_CHANGE_CALLS, true);
-
         TransportMock transportMock = setUpInitializedTransport(mTransport);
         when(transportMock.transport.getCurrentRestoreSet()).thenReturn(1234L);
         when(transportMock.transport.isAppEligibleForBackup(