fix($animate): correctly access minErr

ngMinErr is available during unit tests, but not in the build. There's
currently no way to catch these access errors in automated testing.

src/ngAnimate/shared.js

@@ -73,6 +73,7 @@ var isPromiseLike = function(p) {
   return p && p.then ? true : false;
 };
 
+var ngMinErr = angular.$$minErr('ng');
 function assertArg(arg, name, reason) {
   if (!arg) {
     throw ngMinErr('areq', "Argument '{0}' is {1}", (name || '?'), (reason || "required"));