web_dev_style: update js_checker to import/use eslint.Run()

R=dpapad@chromium.org
BUG=916782

Change-Id: I39b438178bd0f39fbfb0160a8735ffd0f06fb147
Reviewed-on: https://chromium-review.googlesource.com/c/1394365
Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Commit-Queue: Dan Beam <dbeam@chromium.org>
Cr-Commit-Position: refs/heads/master@{#619793}
1 file changed