Minor changes to the WindowGlass theme

additional styles to account for taskbar updated paths

affects search, instead of visual states each search style gets its own target now. 

can no longer use visual states with search on taskbar, as search pill still crashes when customized, and can no longer be set separately from search icon 

Shouldn't affect users that do not have this updated taskbar search, which has now moved under Taskbar.TaskbarExtensionElement in the update