Insert Media modal: IE 7, 8, and 9 issues

[SergeyBiryukov]

1. The vertical line on the left is displayed in IE 9, but not in IE 8 (see 22446.ie8.png​, 22446.ie9.png​).
2. "Drop files anywhere to upload" shouldn't be displayed in IE 7/8/9, as it doesn't support drag-and-drop (at least it doesn't on wp-admin/media-new.php).
3. IE 7 needs some attention for the gallery view, see 22446.ie7_gallery.png​
4. IE 7 doesn't display the selected images (22446.ie7_selected_images.png​) and in IE 9 you can see the second line (22446.ie9_selected_images.png​)
5. In IE 7 and IE 8 you can't see which image is currently selected (blue border is missing), see 22446.ie8_selected_image.png​