Tests for Model::ClearCachedResults + puts multi-contact tests in separate unit tests.
Tests for Model::ClearCachedResults + puts multi-contact tests in separate unit tests.

sheim/drake,sheim/drake,billhoffman/drake,sheim/drake,sheim/drake,billhoffman/drake,billhoffman/drake,billhoffman/drake,billhoffman/drake,sheim/drake,billhoffman/drake,sheim/drake,sheim/drake,billhoffman/drake,sheim/drake,billhoffman/drake