bug#17210: 24.3.50; help mode [back] link to a C-h b keybind listing fails with message "Current buffer is not in Help mode"

[martin rudalics <rudalics@gmx.at>]

 > Can you tell why you replaced a literal "*Help*" with a call to
 > help-buffer?  That change was part of your pixel-resizing changes, but
 > it doesn't sound related to me, and the ChangeLog entry doesn't
 > provide any explanations to convince me otherwise.

I tested `window-text-pixel-size' mostly by switching forward and
backward between help buffers because these are the only ones here whose
text size is not an integral multiple of the nominal character size.  In
the course of testing I found some problems with help buffers and fixed
them on the fly.

Later, when I installed the pixelwise changes, I was afraid to back out
some related ones like the one we talk about here.  But note that the
bug which is the subject of the current thread was implicitly caused by
reverting a behavior erroneously introduced in Emacs 24.3 (see the
threads of bug#16816 and bug#17007 for details).

 > Also, describe-bindings-internal is only called from this single
 > place, so I see no reason to support some other help buffers.  Do you?

I think Stefan explained that meanwhile.

martin