eclass-overlay: add netperf user and group

netperf-2.7 ebuild (upgrade depends on this CL) requires netperf user and group.

BUG=chromium:806326
TEST=cd /mnt/host/source/src/third_party/portage-stable/net-analyzer/netperf
     <cherry-pick from https://chromium-review.googlesource.com/877415>
     # assumes test/dev image already deployed on $B1/$B2
     cros deploy $B1 net-analyzer/netperf
     cros deploy $B2 net-analyzer/netperf

     netserver -V and netperf -V on respective machines should report:
     Netperf version 2.7.0

     (beware of /usr/local/bin vs /usr/bin/)

     On $B1: "netserver" and "iptables -I INPUT 1 -j ACCEPT"
     On $B2:
         NETPERF=/usr/bin/netperf
         $NETPERF -H 192.168.xx.yy -t TCP_MAERTS -B "RX Mbps" -- -s 256K -S 256K

Change-Id: I63d734228122a2173b051f89d09d22c29b830966
Reviewed-on: https://chromium-review.googlesource.com/889502
Commit-Ready: Grant Grundler <grundler@chromium.org>
Tested-by: Grant Grundler <grundler@chromium.org>
Reviewed-by: Grant Grundler <grundler@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
(cherry picked from commit 60d41e49221955846e347e5642f03cff188d31d7)
Reviewed-on: https://chromium-review.googlesource.com/902706
Commit-Queue: Grant Grundler <grundler@chromium.org>
diff --git a/profiles/base/accounts/group/netperf b/profiles/base/accounts/group/netperf
new file mode 100644
index 0000000..8a4f8b9
--- /dev/null
+++ b/profiles/base/accounts/group/netperf
@@ -0,0 +1,3 @@
+group:netperf
+gid:20105
+users:netperf
diff --git a/profiles/base/accounts/user/netperf b/profiles/base/accounts/user/netperf
new file mode 100644
index 0000000..bccdb75
--- /dev/null
+++ b/profiles/base/accounts/user/netperf
@@ -0,0 +1,6 @@
+user:netperf
+uid:20105
+gid:20105
+gecos:Network Performance measurement tool
+home:/dev/null
+shell:/bin/false