Fixes PR14801 - preprocessor directives shouldn't be indented

Uses indent 0 for macros for now and resets the indent state to the
level prior to the preprocessor directive.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@171639 91177308-0d34-0410-b5e6-96231b3b80d8