V8 Buildbot: Switch experimental builder and tester.
V8 Buildbot: Switch experimental builder and tester.

Let the tester run on slaves that are expected to be often idle and available, so that the testers can start immediately after getting a trigger from the builder.

BUG=355369
TBR=phajdan.jr@chromium.org

Review URL: https://codereview.chromium.org/262233003

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@268186 0039d316-1c4b-4281-b951-d872f2087c98

eunchong/build,eunchong/build,eunchong/build,eunchong/build