title: Where is UnitTestAssertException defined?
body: <p>Trying to catch <code>UnitTestAssertException</code> per the advice given <a href="https://stackoverflow.com/a/9382707/1399272">here</a> (working with Visual C++ 2012).  <a href="https://msdn.microsoft.com/en-us/library/microsoft.visualstudio.testtools.unittesting.unittestassertexception(v=vs.110).aspx" rel="nofollow noreferrer">The MSDN documentation</a> indicates it is in namespace <code>Microsoft.VisualStudio.TestTools.UnitTesting</code>, but what header do I need to include?</p>