split syntax highlighting of macros from keywords and comments,
allowing us to use a cheaper means to highlight keywords and making
it so that comments won't foul up macro expansions.

Start highlighting macro expansions.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@49779 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed