QA test to be automated: MDLQA-9822

Testing instructions

1. Create a course and ensure it has a Recent Activity block.
2. Add a folder resource.
3. Add files to the folder resource (add some png, together with other, non-graphic files).
4. Click on "Save and return to course" button.
5. Verify that the files are listed in the Recent Activity block and that you can download the files.
6. Follow the "Full report of recent activity..." link in the block.
7. Verify that:
   1. There is a section for the folder resource created (with link to the resource).
   2. The same new files are listed under the section.
   3. The files can be downloaded.
   4. Image files show a mini-preview of the image as icon. Non-image files show the corresponding file type icon.