Mobbuild: Create mobbuild user.

Adding a new user to run mobbuild processes.

BUG=chromium:414494
TEST=(1) Can kick off processes as mobbuild and can ssh in as mobbuild using
         authorized keys.
     (2) security_AccountsBaseline passes.

Change-Id: Icf8386c4fa5610a1ddc45da062a4223d5f46e472
Reviewed-on: https://chromium-review.googlesource.com/222254
Commit-Queue: Prathmesh Prabhu <pprabhu@chromium.org>
Tested-by: Prathmesh Prabhu <pprabhu@chromium.org>
Reviewed-by: Simran Basi <sbasi@chromium.org>
diff --git a/profiles/base/accounts/group/mobbuild b/profiles/base/accounts/group/mobbuild
new file mode 100644
index 0000000..2802cc6
--- /dev/null
+++ b/profiles/base/accounts/group/mobbuild
@@ -0,0 +1,3 @@
+group:mobbuild
+gid:261
+users:mobbuild
diff --git a/profiles/base/accounts/user/mobbuild b/profiles/base/accounts/user/mobbuild
new file mode 100644
index 0000000..d76f485
--- /dev/null
+++ b/profiles/base/accounts/user/mobbuild
@@ -0,0 +1,7 @@
+user:mobbuild
+uid:261
+gid:261
+password:x
+gecos:mobbuild user
+home:/home/mobbuild
+shell:/bin/bash