Store location of definition of functions...

...instead of declarations. Declarations will now be used only as
fallback if definition cannot be found for some reason.

Change-Id: I1b79622e70d2227cd715f3d82b12f36997080a2e
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@theqtcompany.com>
Reviewed-by: Niels Weber <niels.weber@theqtcompany.com>