Bump waiting time to avoid test failures

spec/chatbox.js

@@ -1228,7 +1228,7 @@
 
                     test_utils.waitUntil(function () {
                         return view.$el.find('.chat-content').find('.chat-message img').length;
-                    }, 300).then(function () {
+                    }, 500).then(function () {
                         expect(view.sendMessage).toHaveBeenCalled();
                         var msg = view.$el.find('.chat-content').find('.chat-message').last().find('.chat-msg-content');
                         expect(msg.html()).toEqual('<img src="'+message+'" class="chat-image">');
@@ -1236,7 +1236,7 @@
                         test_utils.sendMessage(view, message);
                         return test_utils.waitUntil(function () {
                             return view.$el.find('.chat-content').find('.chat-message img').length === 2;
-                        }, 300)
+                        }, 500)
                     }).then(function () {
                         expect(view.sendMessage).toHaveBeenCalled();
                         var msg = view.$el.find('.chat-content').find('.chat-message').last().find('.chat-msg-content');