When building the iOS app with optimisation (using the Release
configurtaion), the linker will not include functions even if they
have been marked with __attribute__ ((visibility("default"))). To get
such a function included, you need an actual reference to it.

Sure, I could probably do some other trick instead. Or I could use a
table and loop here instead of a sequence of if statements. Later.

Change-Id: I86fa38838f242fd1ac251da6e3885f5b166963d3