In commit 9bd22dc0, I introduced an API to load an arbitrary
.desktop file, not necessarily from the menu path. It turns
out this function was broken because it created ShellApp instances
that were *different* from ones that were cached normally.
As far as I can tell, we didn't initially use it. Then later
Util.spawnDesktop was created which used this function.
Remove this broken function and all callers; if we're loading
.desktop files from *outside* the menu path, we can look at
readding.
This patch also kills off Util.spawnDesktop in favor of callers
talking to ShellAppSystem directly, now that the latter reports
errors.
https://bugzilla.gnome.org/show_bug.cgi?id=644402
fea8b6da2f