bug#13061: 24.3.50; regressions: 1) Redefining a function should cancel`debug-on-entry',2) doc

[Drew Adams]

> > It is so simple to hit C-M-x when debugging and modifiying 
> > a function that has `debug-on-entry'.  Doing that should
> > (obviously) cancel opening the debugger on entry.  This has
> > always been the behavior in Emacs, and it should be a no-brainer.
> 
> Just one comment from another user: I like the opposite (that is, the
> new) behavior.  It always annoyed me that e.g. loading file sources
> canceled any according `debug-on-entry' in effect.  I prefer to use
> `cancel-debug-on-entry' explicitly.
> 
> Maybe the behavior could be made configurable?

+1 - users use Emacs differently.

But the default behavior should be the longstanding behavior.
There is no reason to change that.