Use std::vector for TranslatedAttribs. This allows us to cache a std::vector between calls, and avoids us calling allocation/constructors for locals, which saves us some time. It also allows us to use the vector's size to limit the range of attribs we look at. BUG=angleproject:959 Change-Id: I799ed6c92fa8fca96e92e235b125a11d2d551aab Reviewed-on: https://chromium-review.googlesource.com/277286 Reviewed-by: Geoff Lang <geofflang@chromium.org> Tested-by: Jamie Madill <jmadill@chromium.org>