* Implement basic functionality
* Change approach.
move filter controls to manager
edit redrawing to always work with new GetVisibleItemCount() and GetVisibleItemByIndex() calls
* Fix performance issues. Some refactoring.
* Handle toggleAll correctly
* Handle dangling elements when filter is on
Make an item visible if it has at least one visible subitem
* Support filtering for selected and shouldRename
* Refactor for readability, remove useless member from PowerRenameUI
* Change variable names in PowerRenameUI for clarity
Use wrapper function RedrawItems() and SetItemCount() for consistency
* Handle result value properly in getVisibleItemByIndex()
* Add FlagsApplicable filter
* Add visual indication of filters
* Improve performance
Check if no filter is selected
Call SetItemCount() only when necessary
* Refactor for readability
* Get lock in setVisible()
* Change function names to camel case
* Change function names to start with uppercase
* Change filter behaviour when search area is empty
Show all elements when search area is empty and ShouldRename filter is selected
Avoid warnings
* Resolve conflicts
