bug#20774: auto-fill doesn't work properly when first-line prefix differs in adaptive-fill-mode

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Samuel Freilich <sfreilich@google.com> writes:

> Yes, that's correct. Sorry for getting that wrong in my initial
> description of the bug. That's the same as the indentation behavior
> with auto-fill-mode disabled. A hanging indent is not assumed with
> only one line.

Ah okay.  The patch looks fine (apart from the indentation being off, I
assume because you had tab-width = 4).  Would you mind adding a commit
message?  (See CONTRIBUTE for the format.)

If you're feeling up to it, a test would be nice too.

Since you're sending from a google.com address, I understand the
copyright assignment is covered under Google's blanket agreement, is
that right?