title: vue.js prevent line breaks when using v-on keydown
body: <p>I have a textarea that is bound to a v-model.
  Upon pressing enter, I submit the textarea value and clear the model value.
  The problem is that after that submit function runs, I'm left with the textarea having a line break as it registers the final enter key.</p>
  
  <p>I've tried binding onkeyup | key 'enter' to return false to no avail.</p>
  
  <pre><code>&lt;textarea class="chat-input" v-model="message" 
      v-on="keydown: onSubmit(chat, $event) | key 'enter'"&gt;
  &lt;/textarea&gt;
  </code></pre>
  
  <p>is there a way I can prevent the line break from occurring after my submit function runs?</p>