[Wallpaper Picker] Cleaned UI artefacts in Surprise Me Mode.

In Surprise Me mode, changes are: 
- Top categories don't highlight anymore on Hover
- Online Wallpaper Attributes (author + url + thumbnail) are not displayed
- Selected Item Checkmark is not displayed
- "Add New" button is not highlighted on Hover and don't prompt user anymore.
- White Outline on thumbnails is not displayed.

Screenshot: http://i.imgur.com/UPhSQZS.jpg

Review URL: https://codereview.chromium.org/183853030

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255379 0039d316-1c4b-4281-b951-d872f2087c98
Switch Quickoffice to new internal repo

BUG=338855
TEST=manual
NOTRY=true
R=jhawkins@chromium.org, zork@chromium.org

Review URL: https://codereview.chromium.org/187983003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255380 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 255380