Submit type cherry-pick not supported

[m-linner-ericsson]

Description

When using the cherry-pick submit type with empty changes we will not behave correctly. Gerrit will always send Gerrit events even though the master branch is untouched. This happens when you create an empty change.

Motivation

Exemplification

This happens when you create and submit an empty change and have submit type cherry-pick. This is seen in the integration tests. Currently this integration is not part of the test suite (its commented out).

Benefits

The Gerrit plugin becomes more robust

Possible Drawbacks

Time-consuming to come up with a solution