build repo: add matching waterfall builder for infra/build_repo_real_try.
build repo: add matching waterfall builder for infra/build_repo_real_try.

R=phajdan.jr@chromium.org
BUG=590806

Review URL: https://codereview.chromium.org/1754623002

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@299024 0039d316-1c4b-4281-b951-d872f2087c98

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