Messaging: Implement per conversation channels. Update API level to 28.

* Get rid of in-app settings for notifications, replaced by channels features
* Remove all the notification plumbing and dead code

Test: m, manual

Signed-off-by: Luca Stefani <luca.stefani.ge1@gmail.com>
Signed-off-by: Joey <joey@lineageos.org>
Signed-off-by: Danny Baumann <dannybaumann@web.de>
Signed-off-by: Arne Coucheron <arco68@gmail.com>
Signed-off-by: Lyubo <lyubodzhamov@gmail.com>
Change-Id: Idb39ca32751d40b3376934775d2119dd6cc7e297

tests/src/com/android/messaging/datamodel/action/ReadWriteDraftMessageActionTest.java

@@ -113,7 +113,7 @@ public class ReadWriteDraftMessageActionTest extends BugleTestCase {
         participants.add(ParticipantData.getFromRawPhoneBySystemLocale(participantNumber));
 
         final String conversationId = BugleDatabaseOperations.getOrCreateConversation(db, threadId,
-                senderBlocked, participants, false, false, null);
+                senderBlocked, participants);
         assertNotNull("No conversation", conversationId);
         return conversationId;
     }
@@ -189,7 +189,7 @@ public class ReadWriteDraftMessageActionTest extends BugleTestCase {
         participants.add(ParticipantData.getFromRawPhoneBySystemLocale(Long.toString(phoneNumber)));
 
         conversationId = BugleDatabaseOperations.getOrCreateConversation(db, threadId,
-                senderBlocked, participants, false, false, null);
+                senderBlocked, participants);
         assertNotNull("No conversation", conversationId);
 
         final MessageData actual = BugleDatabaseOperations.readDraftMessageData(db, conversationId,