bug#35036: 27.0.50; delete-indentation removes all blank lines

[Alex Branham]

After 8fa94a1ecc18a41ca2738f438b3fbc817c9fdc82, delete-indentation
removes all blank lines so that a buffer:

one


two|


with | as point, M-x delete-indentation results in:

one two

whereas before it would result in:

one

two

This seems contrary to the documentation, which states, "Join this line
to previous and fix up whitespace at join." and also the NEWS entry,
"When there's no active region, the command works on the current and the
previous or the next line, as before."

I'm happy to submit a patch fixing this, but should it change the
documentation to match the new behavior, or fix the code so that the
behavior is unchanged?

Also, is the patch in Bug#35021 going to get applied soonish? If so I'll
hold off in order not to create conflicts...

Thanks,
Alex