[analyzer] Handle 'SomeVar.SomeEnumConstant', which is legal in C++.

This caused assertion failures analyzing LLVM.

<rdar://problem/12560282>

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@166529 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed