`gimp_unit_store_get_value()` clashes with the `get_value()` method of
its parent class GtkTreeStore. This means trouble for bindings, as seen
here in some pseudocode:
```vala
var unit_store = new Gimp.UnitStore();
// Which function are we referencing here, the one from GtkTreeStore or
// the one from GimpUnitStore? Worse, they both have different arguments
unit_store.get_value( ... )
```
The GIR parser is giving warnings because both e.g. a signal, a
corresponding vfunc and a method emitting it are named
"channel_changed", which can and will give issues in some bindings.
The easiest option is to follow the general convention of starting the
signal emitters with `emit_`, which also makes clear the intention of
the method.