fix(a): Opera click event

Fixes Opera click event behavior.
closes https://github.com/angular/angular.js/issues/1225, https://github.com/angular/angular.js/issues/1729, https://github.com/angular/angular.js/issues/1651, https://github.com/angular/angular.js/issues/1674, https://github.com/angular/angular.js/issues/1662