title: why does the change event activates in a v-text-field when pressing enter, even if I didn't change anything?
body: <p>Why does the <code>@change</code> event activates in a <code>v-text-field</code> when pressing enter, even if I didn't change anything?</p>
  
  <p>HTML</p>
  
  <pre><code>&lt;div id="app"&gt;
    &lt;v-app&gt;
      &lt;v-content&gt;
        &lt;v-container&gt;
            &lt;v-text-field
               @change="onChange"
               slot="input"
               label="Edit"
               v-model="test"
               single-line
            &gt;&lt;/v-text-field&gt;
        &lt;/v-container&gt;
      &lt;/v-content&gt;
    &lt;/v-app&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>JS</p>
  
  <pre><code>new Vue({
    el: '#app',
    data: () =&gt; ({
      test: 'test'
      //
    }),
    methods: {
      onChange () {
        console.log('changed')
      }
    }
  })
  </code></pre>
  
  <p>For example,if I press enter without changing anything, then the onChange event shouldn't print "changed" because it's the same string ('test' in this example).</p>
  
  <p>You can see this pen for example: <a href="https://codepen.io/jdash99/pen/aaEYLB?editors=1111" rel="nofollow noreferrer">https://codepen.io/jdash99/pen/aaEYLB?editors=1111</a></p>