[Qt] SpeedBtn of TEditButton steals focus

Original Reporter info from Mantis: Blaazen @Blaazen

• Reporter name: Vojtech Cihak

Description:

When edit of TEditButton is focused and associated speedbtn is clicked, Edit looses focus and focus seems to be nowhere.

It does not happen in GTk2 (1.5) and in Wine (1.4 RC3).

Steps to reproduce:

1. Run demo.
   
2. Set focus to Edit part of TEditButton
   
3. Click associated button.

For comparison, I added standalone Edit and standalone SpeedBtn where it works well (on all mentioned platforms).

Additional information:

Lazarus 1.5 r49022M FPC 3.1.1 x86_64-linux-qt

Mantis conversion info:

• Mantis ID: 28090
• OS: Linux
• OS Build: Chakra 64-bit
• Build: 49022
• Platform: amd64
• Version: 1.5 (SVN)
• Fixed in revision: 49026 (#373d7060)