Names are immutable, so the fixed-sized arrays can be replaced with
variable-length ones to save memory (especially on internal tree nodes).
Signed-off-by: Greg Hackmann <ghackmann@google.com>
(cherry picked from commit 492ce95d9f6149137cb5b63c55cf2b3cdbe51e5e)
Change-Id: Ib074192d1b71150233d78c58e9ffcf7ecf688b6b