LoadRoomMembers: handle room member event a bit more efficiently

matrix-sdk-android/src/main/java/org/matrix/android/sdk/internal/session/room/membership/RoomMemberEventHandler.kt

@@ -83,23 +83,19 @@ internal class RoomMemberEventHandler @Inject constructor(
             userId: String,
             roomMember: RoomMemberContent
     ) {
-        val roomMemberEntity = RoomMemberEntityFactory.create(
-                roomId,
-                userId,
-                roomMember,
-                // When an update is happening, insertOrUpdate replace existing values with null if they are not provided,
-                // but we want to preserve presence record value and not replace it with null
-                getExistingPresenceState(realm, roomId, userId)
-        )
-        realm.insertOrUpdate(roomMemberEntity)
-    }
-
-    /**
-     * Get the already existing presence state for a specific user & room in order NOT to be replaced in RoomMemberSummaryEntity
-     * by NULL value.
-     */
-    private fun getExistingPresenceState(realm: Realm, roomId: String, userId: String): UserPresenceEntity? {
-        return RoomMemberSummaryEntity.where(realm, roomId, userId).findFirst()?.userPresenceEntity
+        val existingRoomMemberSummary = RoomMemberSummaryEntity.where(realm, roomId, userId).findFirst()
+        if (existingRoomMemberSummary != null) {
+            existingRoomMemberSummary.displayName = roomMember.displayName
+            existingRoomMemberSummary.avatarUrl = roomMember.avatarUrl
+            existingRoomMemberSummary.membership = roomMember.membership
+        } else {
+            val roomMemberEntity = RoomMemberEntityFactory.create(
+                    roomId,
+                    userId,
+                    roomMember
+            )
+            realm.insert(roomMemberEntity)
+        }
     }
 
     private fun saveUserEntityLocallyIfNecessary(