ngMessagesInclude not animated

[stunaz]

ng-message which are within ng-messages-include don't get the class 'md-input-messages-animation'.

ie this does not work well :

<md-input-container class="md-block">
    <input md-maxlength="30" required name="description" g-model="project.description">
    <div ng-messages="projectForm.description.$error">
        <div ng-messages-include="errors-message.html"></div>
    </div>
</md-input-container>

where errors-message.html contains:

<div ng-message="required">This is required.</div>
<div ng-message="md-maxlength">The name has to be less than 30 characters long.</div>

[aeby]

This is probably related to #6810