gnucash maint: Bug 797928 - Since last run asks for security price when no shares traded

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash/commit/f7f35fae (commit)
	from  https://github.com/Gnucash/gnucash/commit/cd355c20 (commit)



commit f7f35faefe7a19ac70871340cda034454f511ae6
Author: John Ralls <jralls at ceridwen.us>
Date:   Mon Apr 19 14:23:16 2021 -0700

    Bug 797928 - Since last run asks for security price when no shares traded
    
    Refactor a bit to ensure that the same price variable names and transaction
    currency is used for both extracting the variables and retrieving
    any required exchange rates, and that splits with no formula are
    ignored in both cases.



Summary of changes:
 libgnucash/app-utils/gnc-sx-instance-model.c | 91 ++++++++++++++++++----------
 1 file changed, 60 insertions(+), 31 deletions(-)