Insert inferred timer updates before the corresponding message

js/models/conversations.js

@@ -179,17 +179,17 @@
         }
     },
 
-    addExpirationTimerUpdate: function(time, source) {
-        var now = Date.now();
-        this.save({ expireTimer: time });
+    addExpirationTimerUpdate: function(expireTimer, source, received_at) {
+        received_at = received_at || Date.now();
+        this.save({ expireTimer: expireTimer });
         var message = this.messageCollection.add({
             conversationId        : this.id,
             type                  : 'outgoing',
-            sent_at               : now,
-            received_at           : now,
+            sent_at               : received_at,
+            received_at           : received_at,
             flags                 : textsecure.protobuf.DataMessage.Flags.EXPIRATION_TIMER_UPDATE,
             expirationTimerUpdate : {
-              expireTimer    : time,
+              expireTimer    : expireTimer,
               source         : source
             }
         });

js/models/messages.js

@@ -376,10 +376,13 @@
                         }
                         if (dataMessage.expireTimer) {
                             if (dataMessage.expireTimer !== conversation.get('expireTimer')) {
-                              conversation.addExpirationTimerUpdate(dataMessage.expireTimer, source);
+                              conversation.addExpirationTimerUpdate(
+                                  dataMessage.expireTimer, source,
+                                  message.get('received_at'));
                             }
                         } else if (conversation.get('expireTimer')) {
-                            conversation.addExpirationTimerUpdate(0, source);
+                            conversation.addExpirationTimerUpdate(0, source,
+                                message.get('received_at'));
                         }
 
                         var conversation_timestamp = conversation.get('timestamp');