SRX300 series VLAN interface

I have been configuring an SRX320 for the first time.

[edit vlans]
root@lab-01# run show version
Hostname: lab-01
Model: srx320
Junos: 15.1X49-D45
JUNOS Software Release [15.1X49-D45]

I noticed that under a vlan I am unable to to put a vlan L3 interface on it. 

[edit vlans]
root@lab-01# set v-100 l3-interface vlan.100
error: l3-interface: 'vlan.100': Only IRB interface is supported, e.g. irb.10

[edit vlans]
root@lab-01# show
v-100 {
vlan-id 100;
}

As you can see it refuses to add it. I tried using a IRB interface instead but this is not routable as stated in this link:

http://www.juniper.net/documentation/en_US/junos12.3x48/topics/concept/security-mixed-mode-understanding.html

How do you get a L3 interface onto a VLAN on the SRX300 series?