Google Docs gview viewer retired?
<p>I'm using the Google Docs viewer in multiple places on a few different websites.  This morning, none of them appear to be working and the raw URL returns a 400 error from Google.  Does anyone know if this service has been retired?  If so, are there other lightweight, entirely client side alternatives?
Here's an example that doesn't display for me:</p>

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<pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;iframe src="http://docs.google.com/gview?url=http://www.danburyschools.org/Downloads/2016FallSportsSchedulesD.pdf&amp;embedded=true" style="width:718px; height:950px;" frameborder="0"&gt;&lt;/iframe&gt;</code></pre>
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<p>It was working a few days ago.  Thanks for your help!</p>