Fix ignoring files in PRESUBMIT on Windows
Fix ignoring files in PRESUBMIT on Windows

When comparing filenames, PRESUBMIT didn't exclude files listed in .eslintignore from formatting, because .eslintignore contains forward slashes, but all the files are using native OS-level slashes, so any comparisons failed.

This fixes it by normalising all paths found in .eslintignore.

Change-Id: I9f5cd3cbf15b4b27677968747cf349cde2aed1b3
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/1872596
Auto-Submit: Ingvar Stepanyan <62070607b8a20742f77a132d590706c0c02d8f9a@google.com>
Reviewed-by: Tim van der Lippe <dba8716ee7f8d16236046f74d2167cb94410f6ed@chromium.org>
Reviewed-by: Yang Guo <1cf0af8245a3a17a632a2c73531392b0f9761c76@chromium.org>
Commit-Queue: Yang Guo <1cf0af8245a3a17a632a2c73531392b0f9761c76@chromium.org>

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