Codebase Browser
chromium
Go to App

chromium/third_party/blink/web_tests/transforms/2d/zoom-menulist.html 

<html>
<body onload="document.body.style.zoom = 1.5;">
<h1>Zooming Menu List</h1>

<select style="zoom:3"><option>One<option>Two<option>Three<Option>Four</select>