<span ng-if="!isDataIcon" aria-hidden="true" class="font-icon {{icon}}"></span>
<img ng-if="isDataIcon" src="{{icon}}">
<span ng-if="!isDataIcon" aria-hidden="true" class="font-icon {{icon}}"></span>
<img ng-if="isDataIcon" alt="" ng-src="{{icon}}">

Fix incorrect Content-Type in some Web Console responses
Fix incorrect Content-Type in some Web Console responses

* Set application/json Content-Type for config.js
* Use `ng-src` rather than `src` for custom data icons

Fixes #2652
