Allows using sizeof() on the class constants and reduces space usage by a pointer. Bug: None Change-Id: Ie919b13094903d50bdadc92b23a5aa5b6cc100ec Reviewed-on: https://chromium-review.googlesource.com/581878 Reviewed-by: Tommi <tommi@webrtc.org> Reviewed-by: Danil Chapovalov <danilchap@webrtc.org> Commit-Queue: Steve Anton <steveanton@webrtc.org> Cr-Commit-Position: refs/heads/master@{#19113}