[analyzer] DynTypes: Add a test for improper cast performed by  user.

Dynamic type inference does the right thing in this case. However, as
Jordan suggested, it would be nice to add a warning here as well.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@161365 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed