split macro expansion support out of Preprocessor.cpp into PPMacroExpansion.cpp
Rename Directives.cpp -> PPDirectives.cpp since it implements part of the
Preprocessor class.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@48078 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed