Move capability values from gl::Extensions to gl::Caps. Several extensions stored extra information in the wrong structure. Move them to the Caps structure in prepraration for auto-generating the Extensions struct. Bug: angleproject:6379 Change-Id: If5643b72039e299cb0f7c49591d13b3c7cd8a36c Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3158403 Reviewed-by: Cody Northrop <cnorthrop@google.com> Reviewed-by: Jonah Ryan-Davis <jonahr@google.com> Commit-Queue: Jamie Madill <jmadill@chromium.org>