toCommonSwingV() is only called when SwingAuto is false, but it converts
kGreeSwingLastPos to kAuto. It doesn't make sense, because:
1. kGreeSwingLastPos means that swinging is stopped (i.e. the shutter
remains in its last position), which corresponds to kOff.
2. kAuto shouldn't be returned from this function at all, because it's
handled separately in toCommon() when SwingAuto is true.
3. As can be seen in setSwingVertical(), when automatic is false, the
valid set of positions includes kGreeSwingLastPos, but not
kGreeSwingAuto.
Fix the logic by amending toCommonSwingV() according to the
considerations above. It fixes parsing of received IR packets when the
user disables vertical swinging from the remote (tested with YAP1FB).
For consistency and robustness, educate setSwingVertical() and
convertSwingV() about the supported kGreeSwingLastPos mode.
Add a unit test for the described bug.
8a049f5785