message list: Stub with Error instead of asserting zero calls in tests.
message list: Stub with Error instead of asserting zero calls in tests.

This is a cleaner way of testing that the function
is not called, than using counters.

This code was added in 9cb41c2976b83ea81b87757dd3a4c942ee7b71c1.

zulip/zulip,hackerkid/zulip,rht/zulip,zulip/zulip,rht/zulip,punchagan/zulip,kou/zulip,eeshangarg/zulip,rht/zulip,zulip/zulip,hackerkid/zulip,hackerkid/zulip,punchagan/zulip,andersk/zulip,zulip/zulip,kou/zulip,hackerkid/zulip,zulip/zulip,eeshangarg/zulip,punchagan/zulip,andersk/zulip,kou/zulip,punchagan/zulip,kou/zulip,rht/zulip,andersk/zulip,eeshangarg/zulip,rht/zulip,andersk/zulip,punchagan/zulip,hackerkid/zulip,eeshangarg/zulip,hackerkid/zulip,andersk/zulip,rht/zulip,andersk/zulip,kou/zulip,hackerkid/zulip,rht/zulip,punchagan/zulip,kou/zulip,eeshangarg/zulip,zulip/zulip,kou/zulip,punchagan/zulip,zulip/zulip,eeshangarg/zulip,eeshangarg/zulip,andersk/zulip