GitLab

Use enum class instead of enum for views::SliderChangeReason.
enum class is more type safety.

Bug: 940736
Change-Id: I396a74e79cdf6da52163d875fcceffa20920968f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2128033Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Peter Kasting <pkasting@chromium.org>
Commit-Queue: Hwanseung Lee <hs1217.lee@samsung.com>
Cr-Commit-Position: refs/heads/master@{#755194}