Messages With Hidden Unicode Chars Fail to Send

Summary

When copying text form other apps, there may be some hidden Unicode control Characters such as "\u0001". Messages containing such characters fail to send in the 4.0 clients. The text below, for example, contains the \u0001 char:

• Is this setup for PE only or
  QA as well?

How it shows up in the client logs:

2016-03-24 10:49:43:201-0300  [223877_1782038@chat.hipchat.com] [WebCore] [DEBUG] [AnalyticsDispatcher: analytics-send-message] {"text":"Is this setup for PE only or \u0001QA as well?","jid":"223877_test_room@conf.hipchat.com","id":1,"time":1458827383.198}

This has also been reported with the invisible UTF8 characters for Escape and Delete, examples of which can be found in this file: UTF8_ESC_Backspace .

Steps to Reproduce

1. Copy the example text above and paste it on the client
2. Try sending the message in any room/chat

Expected Result

The client ignores the control character and sends the message

Actual Result

Workaround

Type the message directly in the client or paste it to a notepad and copy/paste from there.