Show message summary and detail only when they have value

[negberts]

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Current behavior
Summary and detail are always rendered for messages, even when they are null or empty.

<li *ngFor="let msg of value">
                    <span class="ui-messages-summary" [innerHTML]="msg.summary"></span>
                    <span class="ui-messages-detail" [innerHTML]="msg.detail"></span>
</li>

Expected behavior

<li *ngFor="let msg of value">
                    <span *ngIf="msg.summary" class="ui-messages-summary" [innerHTML]="msg.summary"></span>
                    <span *ngIf="msg.detail"  class="ui-messages-detail" [innerHTML]="msg.detail"></span>
</li>

Because of the css-classes, even without a summary the messages are shown with a left-margin for instance.

• PrimeNG version: 4.2.0-rc1