<rdar://problem/11146929>

Enabling support for the wchar_t type.
Without the proper language option setup, clang's ASTContexts will be configured to have wchar_t == int
This patch enables the correct options to make sure that we report wchar_t as itself
Added a test case to make sure we do not regress 

Adding files missing from the previous commit

llvm-svn: 172039