title: toString(): numbers in JSON
body: <p>I have QJsonObject, here is it:</p>
  
  <pre><code>QJsonObject({"key":"1475bee449df002422340510c355a7f8b48ea647","pts":960894,"server":"imv4.vk.com/im1976","ts":1626706149})
  </code></pre>
  
  <p><code>object["key"].toString()</code>  - ok, it returns <code>1475bee449df002422340510c355a7f8b48ea647</code><br />
  <code>object["server"].toString()</code> - ok, it returns <code>imv4.vk.com/im1976</code><br />
  <code>object["ts"].toString()</code> - fail, returns <code>""</code>.<br />
  <code>object["pts"].toString()</code> - fail, returns <code>""</code>.<br />
  <br /><br />
  Yes, i can do <code>QString::number(object["ts"].toInt());</code>, but it isn't solution: value can be greater then <code>MAXINT</code>. Type of <code>object["ts"]</code> is <code>double</code>:</p>
  
  <pre><code>QJsonValue(double, 1626706149)
  </code></pre>
  
  <p>But <code>object["ts"].toDouble()</code> returns <code>1.62671e+09</code>. Any suggestions?</p>