fix: changing the way received timestamp handling happens

app/src/main/java/org/thoughtcrime/securesms/database/Storage.kt

@@ -274,12 +274,7 @@ class Storage(context: Context, helper: SQLCipherOpenHelper) : Database(context,
     }
 
     override fun isMessageDuplicated(timestamp: Long, sender: String): Boolean {
-        val database = DatabaseFactory.getMmsSmsDatabase(context)
-        return if (sender.isEmpty()) {
-            database.getMessageForTimestamp(timestamp) != null
-        } else {
-            database.getMessageFor(timestamp, sender) != null
-        }
+        return getReceivedMessageTimestamps().contains(timestamp)
     }
 
     override fun setUserCount(group: Long, server: String, newValue: Int) {

libsession/src/main/java/org/session/libsession/messaging/sending_receiving/MessageReceiver.kt

@@ -52,7 +52,6 @@ object MessageReceiver {
         // will already be in the database but we don't want to treat the message as a duplicate. The isRetry flag is a simple workaround
         // for this issue.
         if (storage.isMessageDuplicated(envelope.timestamp, GroupUtil.doubleEncodeGroupID(envelope.source)) && !isRetry) throw Error.DuplicateMessage
-        storage.addReceivedMessageTimestamp(envelope.timestamp)
         // Decrypt the contents
         val ciphertext = envelope.content ?: throw Error.NoData
         var plaintext: ByteArray? = null
@@ -101,6 +100,7 @@ object MessageReceiver {
         }
         // Don't process the envelope any further if the message has been handled already
         if (storage.isMessageDuplicated(envelope.timestamp, sender!!) && !isRetry) throw Error.DuplicateMessage
+        storage.addReceivedMessageTimestamp(envelope.timestamp)
         // Don't process the envelope any further if the sender is blocked
         if (isBlock(sender!!)) throw Error.SenderBlocked
         // Parse the proto