Fix hacking check for jsonutils

Hacking checks with logical_lines should use yield not return.

The jsonutils rule was added in:
I86ed6cd3316dd4da5e1b10b36a3ddba3739316d3

Now that the function uses yield, it can trigger twice in dumps (dump
and dump), so look for a '(' at the afterwards. Don't display the '(' at
the end of the error message since its confusing to read.

Change-Id: I277dba08fdd30734409eee36008cebda35886968
Closes-Bug: #1356687
Hacking: a new hacking check was added that used an existing number

Commit 243879f5c51fc45f03491bcb78765945ddf76be8 added in a new hacking
check that used an existing number.

The new number is 324 (and not 323)

Change-Id: I7e604a408387438105c435ad16a1fa3d6491b642
Closes-bug: #1356815
Merge "Fix hacking check for jsonutils"
Merge "Hacking: a new hacking check was added that used an existing number"