[Basic] getColumnNumber returns location of CR+LF on Windows

When fixing a Clang-Tidy bug in D31406,
reuse of FileID enabled the missing highlightRange function.
Assertion in highlightRange failed because the end-of-range column
number was 2 + the last column of a line on Windows.
This fix is required to enable D31406.

Differential Revision: https://reviews.llvm.org/D31713



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@299681 91177308-0d34-0410-b5e6-96231b3b80d8