Erroneous sort call when maximizing window via title bar double-click

[UskovM]

With specific window layouts, a double-click on the title bar mistakenly triggers sorting in Column 1. A reproduction demo project is attached in Vt2Bug.zip.

VTBug2.zip

[UskovM]

I couldn't fix the behavior of TVTHeader.HandleMessage + fWasDoubleClick, so I implemented my own workaround by launching an additional timer on the WM_WINDOWPOSCHANGED event and adding a new tsColumnClickLock state

and processing it into VirtualTrees.Header.pas