update contact list logic to prevent bug.
update contact list logic to prevent bug.

tutsplus/angularjs-for-test-driven-development,StevenPerez/angularjs-for-test-driven-development,cfree/angularjs-for-test-driven-development,rmulder/angularjs-for-test-driven-development,tutsplus/angularjs-for-test-driven-development,cfree/angularjs-for-test-driven-development,StevenPerez/angularjs-for-test-driven-development,rmulder/angularjs-for-test-driven-development