Codebase Browser
chromium
Go to App

chromium/chrome/test/data/chromeos/file_manager/file_input/element.html 

<!doctype html>
<html>
<head>
<style>
 html, body, input { margin: 0px; padding: 0px }
</style>
</head>
<body>
 <input type="file" name="file-input-element">
</body>
</html>