The catch keyword isn't really part of a region, so it's fairly
meaningless to extend into it. This was usually harmless, but it could
crash when catch blocks involved macros in strange ways.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@243066 91177308-0d34-0410-b5e6-96231b3b80d8