Bug#790325: libxaw7: obtaining textSink.textProperties by editres triggers sigsegv in application

["Yuriy M. Kaminskiy" <yumkam@gmail.com>]

Control: tags -1 fixed-upstream

Almost 4 years later, this bug is still present in stretch and buster.

Similar patch was applied upstream (with minor changes) in 2016-01-01, more than three years ago,
commit 4a7626b5127c0eb597cd2b8d0ae3de0286b74d7c

I'd like to point out to commits
ba7321b6a52726cdb9964b82c5111518dc1f437d
and
f5699b698d512bb1060ef53704595d6accf7eb19
from upstream git that fixes other (unrelated) trivial crashing bugs and likely worth backporting.