http://googledevelopers.blogspot.ca/2013/05/an-easier-way-to-save-files-to-google.html
<script src="https://apis.google.com/js/plusone.js"></script>
<div class="g-savetodrive"
data-filename="My Statement.pdf"
data-sitename="My Company Name"
data-src="/path/to/myfile.pdf">
</div>