Remove Chromium builders from build.webkit.org

Remove Chromium builders from build.webkit.org
https://bugs.webkit.org/show_bug.cgi?id=113990

Reviewed by Benjamin Poulain.

Removed.

* BuildSlaveSupport/build.webkit.org-config/config.json:
* BuildSlaveSupport/build.webkit.org-config/master.cfg:
(InstallGtkDependencies):
(RunUnitTests.start):
(RunWebKit2Tests.start):
(Factory.__init__):
(unitTestsSupported):
(TestFactory.__init__):
(BuildAndTestFactory.__init__):
(BuildAndPerfTestFactory.__init__):
(BuildAndPerfTestWebKit2Factory.__init__):
(DownloadAndPerfTestFactory.__init__):
(loadBuilderConfig):
* BuildSlaveSupport/build.webkit.org-config/templates/root.html:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@147981 268f45cc-cd09-0410-ab3c-d52691b4dbfc