jenkinsci/jenkins — pull request #346 by ohtake (2012-01-12 06:45:33+00:00)
Title: [JENKINS-12177] Zero executors on master is no longer valid

This pull request allows zero executors on master.
I am sorry that #298 introduced a new issue [JENKINS-12177](https://issues.jenkins-ci.org/browse/JENKINS-12177).