Main window focus bugs

[frca]

I discovered some minor, but annoying bugs in C::B:
1. When C::B window loses focus, it should hide all code tooltips/code completion ballon help, they are otherwise visible on upper windows because they are probably topmost.
2. C::B should never gain focus by itself. This happens sometimes when compiled application starts that it loses focus immediately. But it happend only in SDL apps yet as I remember, so maybe it is a SDL bug or something else.

These bugs were discovered in WinXP pro.

[Albenejean]

1. When C::B window loses focus, it should hide all code tooltips/code completion ballon help, they are otherwise visible on upper windows because they are probably topmost.

I confirm this is **sometimes** very annoyning.