Removing prog-indentation-context (was: [Emacs-diffs] widen-limits c331b66: Implement buffer-widen-limits functionality)

[Stefan Monnier <monnier@iro.umontreal.ca>]

>> >> [prog-indentation-context]
>> > Should we rip them out, as long as it's not too late?
>> Yes. If nobody beats me to it, I'll revert it in emacs-25 this weekend. 
>> The yet-unfinished discussion aside, it doesn't look ready for 25.1 
>> either way.

FWIW, I think it's a mistake to remove it.  We need to move forward on
multi-mode support, and even if prog-indentation-context is not "the
right way" (I doubt there is such a thing anyway), adapting some major
modes to it will most likely not be wasted time, because it will most
likely make it easier to adapt those modes to whichever other approach
we may switch to in some future.

More importantly, I don't think we'll ever agree on what should be done
in this respect because we'll only know what works and what doesn't
*after* we install it and make it "the official way".

I think any attempt at adding support for multi-mode is inevitably
flawed (unless it is designed from scratch and doesn't intend to try and
work with existing modes) and it's easy to see those flaws.  So we can
only make progress if we (somewhat arbitrarily) pick one candidate and
run with it.  The "run with it" part will hopefully help align the
various major modes, thus making it easier for a second candidate to
make further progress, and so on and so forth.

At least, that was the reason why I decided to go with
prog-indentation-context.  It was not because I thought it was The Right
Way, the final word on the matter.


        Stefan