Added back the gviz_api to the tools deps - will remove it from the main project DEPS in a different patch. Rewired those symlinks too.
Made the build status loader algorithm more scalable. It read in the whole database on each load which is probably unsustainable in the long run. Also, it will now forget bots that have offline for more than ~5 revisions.
Fixed a bug in the coverage tracker.
BUG=
TEST=
Review URL: https://webrtc-codereview.appspot.com/486002
git-svn-id: http://webrtc.googlecode.com/svn/trunk@2039 4adac7df-926f-26a2-2b94-8c16560cd09d