[Preprocessor] Correct internal token parsing of newline characters in CRLF

[Preprocessor] Correct internal token parsing of newline characters in CRLF

Discovered due to a goofy git setup, the test system-headerline-directive.c
(and a few others) failed because the token-consumption will consume only the
'\r' in CRLF, making the preprocessor's printed value give the wrong line number
when returning from an include. For example:

(line 1):#include <noline.h>\r\n

The "file exit" code causes the printer to try to print the 'returned to the
main file' line. It looks up what the current line number is. However, since the
current 'token' is the '\n' (since only the \r was consumed), it will give the
line number as '1", not '2'. This results in a few failed tests, but more
importantly, results in error messages being incorrect when compiling a
previously preprocessed file.

Differential Revision: https://reviews.llvm.org/D37079

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@311683 91177308-0d34-0410-b5e6-96231b3b80d8