Both relays have a permanent and a switched feed to them, the latter is represented by the switch (Red bar facing upwards in that diagram) the ignition switch in this case, when you switch the ignition on the feed energises the relay hence tripping the "switch inside" hence power travels along to to the relay output and hence the rest of the circuit. So with a SPST relay you essentially have two circuits the relay itself (Live and earth) and the live output when the relay is tripped.

You will notice the ground connects to the ECU, this is how control of the fuel pump is obtained through switching the earth of the relay, the same applies to the ECU relay.

Martin