Taskbar buttons are not highlighted when pushed down

Tested On

• ReactOS 0.4.13-dev-563-g0561610-x86-gcc-lin-dbg
• Windows XP SP3 x86

Tested Software

• ReactOS Explorer
• Windows Explorer

Expected Result

• Taskbar button which represents a window is highlighted using tiny pixel checkerboard (<Windoze XP/S2003) or single color (Windoze Vista+) when its window is active or using LMB/RMB.

Observed Result

• Taskbar button is not highlighted when it's pushed down by LMB/RMB action or its window is set as active.