image with empty alt and global aria-attribute should not pass the image-alt rule

[straker]

The following code snippet should not pass the image-alt rule. The problem is that our has-alt check passes as the image has an empty alt, but the image is not considered presentational because of role conflict resolution of the global aria-label attribute.

<img src="img.jpg" id="violation11" alt="" aria-label="" />

[straker]

Tested this in:

• Safari/VO
• IE11/JAWS
• Chrome/JAWS
• Firefox/NVDA

and all report the image as "blank" but not as an image element (just as in a newline character or empty tag). Thus this isn't an accessibility problem.