tree eba95978073335060a413b559e8b885f79a41ebe
parent b9863ce3394ade9101e41a6dab45b66bd2fd0c13
author Natalie Weizenbaum <nweiz@google.com> 1462298096 -0700
committer Natalie Weizenbaum <nweiz@google.com> 1462298096 -0700

Add GroupSet and SetGroup classes.

GroupSet provides a view of the union of a set of sets. SetGroup
provides an easy way to manage a GroupSet in a class context.

R=floitsch@google.com, lrn@google.com

Review URL: https://codereview.chromium.org//1873373002 .