This is a hack to get the demo working with the new 3.0 exception

This is a hack to get the demo working with the new 3.0 exception
infrastructure. As this makes the demo no longer a demo, and especially not a
demo on how to use the llvm exception mechanism, this hack will shortly be
changed to use the new 3.0 exception infrastructure. However for the time being
this demo is an example on how to use the AutoUpgrade
UpgradeExceptionHandling(...) function on < 3.0 exception handling code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140301 91177308-0d34-0410-b5e6-96231b3b80d8