a missing include from CLog.h.
CLog.h referenced most of the core libclang types but never directly
included Index.h that provides them. Previously it got lucky and other
headers were always included first but with the sorting it ended up
first in one case and stopped compiling. Adding the Index.h include
fixes it right up.
llvm-svn: 202810
Manually fix the order of UnwrappedLineParser.cpp as that one didn't
have its associated header as the first header.
This also uncovered a subtle inclusion order dependency as CLog.h didn't
include LLVM.h to pick up using declarations it relied upon.
llvm-svn: 172892