title: Rating star field in a material ui/redux-form framework not setting to blank on double click of value
body: <p>I am working on a react website - with a form frame that uses material ui and redux forms ---</p>
  <p>I've added a rating field -- and it works well - when you click on the same value it will clear the stars - but when I click off the field it returns the old value back --- I've tried to do all sorts from if(type of input.value === string) -- convert to 0 -- and tried to parseFloat on inputchanges -- but I am not sure what is causing the bug</p>
  <p>its using the controlled rating - <a href="https://material-ui.com/components/rating/" rel="nofollow noreferrer">https://material-ui.com/components/rating/</a></p>
  <p><a href="https://codesandbox.io/s/cocky-grass-ccg69" rel="nofollow noreferrer">https://codesandbox.io/s/cocky-grass-ccg69</a></p>
  <pre><code>  &lt;Rating
      {...input}
      name={input.name + &quot;-&quot; + uuid()}
      onChange={(e, value) =&gt; {
        input.onChange(value);
        onHandle(input.name, value);
      }}
      value={parseFloat(input.value, 10)}
      defaultValue={0}
      precision={0.5}
    /&gt;
  </code></pre>
  <p>&quot;if you click on it to set a value - then again to null the stars --- when you focus off the field - like click elsewhere - it returns the old value &quot;</p>