Revert "[clang-format][NFC] Clean up fillRanges() in ClangFormat.cpp (#143236)"

This reverts commit 897ccddcc30cacdfe04ddd622986b50ec963eabc. It
introduced a bug when formatting multiple files in one go. When a
shorter file is passed after a longer one, a stale length from the
previous file seems to be used, triggering an "invalid length (...) is
outside the file" error.

NOKEYCHECK=True
GitOrigin-RevId: 3c02150f02022292645f6238524f0401a6f5014f
1 file changed