Support for showing deleted channel count in settings.

Bug: 36119790
Test: runtest systemui-notification
Change-Id: Ie30243314d64ded66267d0dc85cc0ad940d917f8

core/java/android/app/INotificationManager.aidl

@@ -66,6 +66,7 @@ interface INotificationManager
     ParceledListSlice getNotificationChannels(String pkg);
     ParceledListSlice getNotificationChannelsForPackage(String pkg, int uid, boolean includeDeleted);
     int getNumNotificationChannelsForPackage(String pkg, int uid, boolean includeDeleted);
+    int getDeletedChannelCount(String pkg, int uid);
 
     // TODO: Remove this when callers have been migrated to the equivalent
     // INotificationListener method.

services/core/java/com/android/server/notification/NotificationManagerService.java

@@ -1697,6 +1697,12 @@ public class NotificationManagerService extends SystemService {
                     .getList().size();
         }
 
+        @Override
+        public int getDeletedChannelCount(String pkg, int uid) {
+            enforceSystemOrSystemUI("getDeletedChannelCount");
+            return mRankingHelper.getDeletedChannelCount(pkg, uid);
+        }
+
         @Override
         public ParceledListSlice<NotificationChannelGroup> getNotificationChannelGroupsForPackage(
                 String pkg, int uid, boolean includeDeleted) {

services/core/java/com/android/server/notification/RankingHelper.java

@@ -766,6 +766,23 @@ public class RankingHelper implements RankingConfig {
         return new ParceledListSlice<>(channels);
     }
 
+    public int getDeletedChannelCount(String pkg, int uid) {
+        Preconditions.checkNotNull(pkg);
+        int deletedCount = 0;
+        Record r = getRecord(pkg, uid);
+        if (r == null) {
+            return deletedCount;
+        }
+        int N = r.channels.size();
+        for (int i = 0; i < N; i++) {
+            final NotificationChannel nc = r.channels.valueAt(i);
+            if (nc.isDeleted()) {
+                deletedCount++;
+            }
+        }
+        return deletedCount;
+    }
+
     /**
      * Sets importance.
      */

services/tests/notification/src/com/android/server/notification/RankingHelperTest.java

@@ -722,6 +722,25 @@ public class RankingHelperTest {
         }
     }
 
+    @Test
+    public void testGetDeletedChannelCount() throws Exception {
+        NotificationChannel channel =
+                new NotificationChannel("id2", "name2", IMPORTANCE_LOW);
+        NotificationChannel channel2 =
+                new NotificationChannel("id4", "a", NotificationManager.IMPORTANCE_HIGH);
+        NotificationChannel channel3 =
+                new NotificationChannel("id4", "a", NotificationManager.IMPORTANCE_HIGH);
+        mHelper.createNotificationChannel(pkg, uid, channel, true);
+        mHelper.createNotificationChannel(pkg, uid, channel2, true);
+        mHelper.createNotificationChannel(pkg, uid, channel3, true);
+
+        mHelper.deleteNotificationChannel(pkg, uid, channel.getId());
+        mHelper.deleteNotificationChannel(pkg, uid, channel3.getId());
+
+        assertEquals(2, mHelper.getDeletedChannelCount(pkg, uid));
+        assertEquals(0, mHelper.getDeletedChannelCount(pkg2, uid2));
+    }
+
     @Test
     public void testUpdateDeletedChannels() throws Exception {
         NotificationChannel channel =