Add user and group for Android root

The android root user runs as 655360, create a user and group for that
ID so that the number doesn't need to be hard-coded everywhere.

BUG=b/29259708
TEST=chown a file to android-root on the device

Change-Id: I08826438d4706f79d675c2e0a2e4825521ca90ce
Reviewed-on: https://chromium-review.googlesource.com/363915
Commit-Ready: Dylan Reid <dgreid@chromium.org>
Tested-by: Dylan Reid <dgreid@chromium.org>
Reviewed-by: Junichi Uekawa <uekawa@chromium.org>
Reviewed-by: Ricky Zhou <rickyz@chromium.org>
diff --git a/profiles/base/accounts/group/android-root b/profiles/base/accounts/group/android-root
new file mode 100644
index 0000000..35e6a39
--- /dev/null
+++ b/profiles/base/accounts/group/android-root
@@ -0,0 +1,3 @@
+group:android-root
+gid:655360
+users:android-root
diff --git a/profiles/base/accounts/user/android-root b/profiles/base/accounts/user/android-root
new file mode 100644
index 0000000..2446d68
--- /dev/null
+++ b/profiles/base/accounts/user/android-root
@@ -0,0 +1,6 @@
+user:android-root
+uid:655360
+gid:655360
+gecos:CrOS android container user
+home:/dev/null
+shell:/bin/false