gnucash maint: Bug 795377 - Reads and saves Gnucash 2.6.19 XML file, then can't reread it, due to bad date in old file

[Geert Janssens]

Updated	 via  https://github.com/Gnucash/gnucash/commit/b761b5a0 (commit)
	from  https://github.com/Gnucash/gnucash/commit/9c4469d0 (commit)



commit b761b5a0dc82ef53e1dc1b7fa50eb196fdd0a4a0
Author: Geert Janssens <geert at kobaltwit.be>
Date:   Sat Apr 28 12:16:52 2018 +0200

    Bug 795377 - Reads and saves Gnucash 2.6.19 XML file, then can't reread it, due to bad date in old file
    
    This commit contains another round of cleanups in the
    timespec to time64 conversion. There were a number of
    false assumptions that time64 = 0 would be a bad date
    in the xml parser. This commit corrects enough of them to
    eliminate the bug. Further cleanup is probably advised but
    can be done at a later stage.



Summary of changes:
 libgnucash/backend/xml/sixtp-dom-generators.cpp    |  2 +-
 libgnucash/backend/xml/sixtp-dom-parsers.cpp       |  8 ++--
 .../backend/xml/test/test-dom-converters1.cpp      |  8 ++--
 libgnucash/engine/gnc-date.cpp                     |  6 +--
 libgnucash/engine/test/test-gnc-date.c             | 46 ++++++++--------------
 5 files changed, 29 insertions(+), 41 deletions(-)