Add own scheduler for sdk builder so that full's are triggered correctly.
Add own scheduler for sdk builder so that full's are triggered correctly.

BUG=chromium-os:16401
TEST=Started buildbot master locally

Review URL: http://codereview.chromium.org/7134077

git-svn-id: 239fca9b83025a0b6f823aeeca02ba5be3d9fd76@88701 0039d316-1c4b-4281-b951-d872f2087c98

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