This inlines several accessors.

Bug: angleproject:2574
Change-Id: I61d223dd2a8f08e5331ccefde02e6ce55f5a607d
Reviewed-on: https://chromium-review.googlesource.com/1067118Reviewed-by: Yuly Novikov <ynovikov@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>