GitLab

Sort pref constants in ChromePreferenceKeys.

This reduces merge conflicts and makes it clearer where new constants
should be placed.

Change-Id: Ibc8cf11c84664ecfa43a4d9e6ddd245b81e7dcbd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1976819
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>
Reviewed-by: Theresa  <twellington@chromium.org>
Cr-Commit-Position: refs/heads/master@{#726520}