bug#10805: 24.0.93; edebug-trace t may cause stuff being inserted into current buffer

[martin rudalics]

> You can check whether the buffer is in `edebug-mode'.  This may require
> some tweaks in edebug.el (e.g. I'm not sure whether edebug-mode is set
> before or after displaying the buffer currently, and IIRC edebug-mode is
> neither a proper major-mode nor a proper minor-mode so you'll probably
> have to detect it in an ad-hoc way, or change edebug.el to use a proper
> major/minor mode).

IIUC `edebug-active' is the variable to consult in this case.  But the
plethora of declared and undocumented variables and aliased functions in
edebug.el is overwhelming.

martin