Bug#297971: dia: Delete key also does not work here

[Ambrose Li]

Sorry for the barrage of comments. While working on a diagram I discovered the following:

- The Delete key deletes objects apparently for all objects, not just "actor" (e.g., press Delete while editing a "use case" object also deletes the object)

- The Backspace key will intermittently stop working. When it stops working, dia will delete text inside the "zoom" box (bottom left of the window).

- When the Backspace key stops working, the arrow keys also stop working and I can no longer type text

- If I use the mouse to click the text in the object when the above happens, typing and arrow keys will work for a couple of keystrokes, and then stop working again.

Obviously, some unknown action will clear this condition, since I had been typing text in objects for about 5 minutes (and no longer able to).

Hopefully this clears up some of the hasty observations I sent in my last 2 comments :-(