Assignment grading screen file submission alt for image and text the same

Issue
Alt - The alt text for the image associated with the file in the file submission column of the grade submissions table is the same as the text in the link to the file.

Example:
<div><img class="icon" alt="hero_and_leander.docx" title="hero_and_leander.docx" src="http://core/theme/image.php/standard/core/1349883032/f/document"> <a href="http://core/pluginfile.php/70/assignsubmission_file/submission_files/7/hero_and_leander.docx?forcedownload=1">hero_and_leander.docx</a> </div>

The alt and title should have empty text or state the type of file such as Word document, which is what the icon actually represents.

Standard Level
WCAG 2 1.1.1 (A) http://www.w3.org/TR/UNDERSTANDING-WCAG20/text-equiv-all.html

Impact
Serious

Example Link
http://demo.moodle.net/mod/assign/view.php?action=grading&id=41&thide=userid

Test Steps

1. Login as teacher
2. Navigate to course CF101
3. Click on Assignment
4. Click on view submissions
5. Tab to the file submissions column and view the source code.