Leave Animation callback overridden by next animation

[sreeramu]

This patch will fix the overriding or loosing the leave callback object of the animation.

Example:

var app = angular.module("app", ['ngMessages', 'ngAnimate']);

app.directive('iholder', ['$animate','$timeout', function($animate,$timeout) {
    return {
        restrict: 'EA',
        scope: {},
        template: '<div class="level1 level2" ng-click="clickHandler()" style="width:100%;height:10em;background-color:red;"></div>',
        replace: true,
        link: function($scope, element, attrs) {
            $scope.clickHandler = function() {
                $animate.leave(element);
                $animate.removeClass(element,'level2');
            }
        }
    }
}]);

In above example removeClass is called as soon as the leave is called so in queueAnimation the the leave animation option (callback) is overridden with the removeClass option so the element is not removed.

This patch will fix the #12249 issue , in this issue leave is called by ngRepeatDirective for removing the element and on destroy ngForm called removeClass so the leave callback is overridden in mergeAnimationOptions so the element is not removed.

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[sreeramu]

I signed it!

[googlebot]

CLAs look good, thanks!

[Narretz]

Hi, thanks for the PR. Would it be possible for you to add a test for this?

[sreeramu]

@Narretz Test script are updated for this bug.

[Narretz]

@matsko can you take a look at this?

[hparfr]

Thanks sreeramu, this PR fix an issue I had (similar to #12161)

[matsko]

@sreeramu I've taken your PR and removed some extra code: #12567

I'm waiting for Travis to be green and then it's in.

Excellent work on this! Thank you for putting in the time.

[sreeramu]

Thanks @matsko