[DiskProbe] select text in Find window

[diver]

Select previously entered text in Find window. e.g. if you search for something, close find window and open it again previously entered text will be not selected as in Mail/StyledEdit/Pe. Also, it would be nice if DiskProbe could save last search and reuse it in other windows or after restart.

[gbl08ma]

Fixes text not being selected on window open

[gbl08ma]

My patch only makes the text become selected. It doesn't save the last search for use when the application is relaunched. I checked other built-in software and it doesn't seem like all apps preserve the find query across launches. This is probably better discussed in a different ticket, as this kind of change is probably better if done to all apps at once, to help with consistency.

[axeld]

Agreed, thanks for the patch! I've applied it in hrev50538.