ngAnimate: 1.2 using ng-class to apply an animation will restart animation secondary class binding updates

[corbanbrook]

  <div class="pane" ng-class="{ open: open, 'edit-mode': isEditing }">

a transition is on the open class to handle sliding in and out the pane, but if a secondary class binding updates, in this example the 'edit-mode' class then entire open animation will restart by adding open-add and open-add-active

[matsko]

This should fix that: #4958