r82477 changed a bunch of Windows-only files, but the Mac builders built it anyway. They should have skipped this revision. For example, <http://build.webkit.org/builders/Leopard%20Intel%20Release%20%28Build%29/builds/32497>.
Turns out r82477 touched webkitdirs.pm, so triggering a build was valid. But it looks like the Mac builders will build in response to any .vcproj/.vsprops/.sln file change, and we should fix that.
r82512 is a better example.
Created attachment 87854 [details]
Mark .vcproj/.vsprops/.sln files as being Windows-only
Committed r82679: <http://trac.webkit.org/changeset/82679>