Current node can be 0.

Task:     - 244529
Details:  - It just doesn't work in Mac menus (at least not with Qt, but
I suspect it's some Mac thingy), so just don't do it.

- on windows, use the recommended way to interrupt a debugged process
- on unix, use SIGTRAP
- assorted minor improvements

rely on the inferior's pid being available. consequently, remove the
bizarre findChild stuff.

fixes interrupting processes with some versions of gdb

RevBy: TrustMe

context

Details:  more consistent with the File menu

Details:  more consistent with the File menu

editor

Conflicts:
	doc/qtcreator.qdoc

workaround for getting the ShortcutOverride twice

Task:     - 246854
RevBy:    - hjk

Details: MinGW compilation

This check is no longer needed since the necessary private headers are
now part of Qt Creator.

Reviewed-by: Friedemann

Details:  re-use lineForPosition

Task:     -
RevBy:    Thorbjorn
AutoTest: -

RevBy:    - dt