Legend color properties missing when changed default color and set top-left color to '0'

[adamws]

There are at least two label color related issues opened:
#315
#214

This one might be related.
Steps to reproduce:

• open empty layout, add two keys
• modify left key:
  • set Legend Color
  • add top left legend, set it color to #000000
  • add other labels

result:

keyboard renders as expected but in Raw data tab, layout is missing color specifiers:

["x\nx\n\n\n\n\nx","x"]

when top left legend color is changed to something else than #000000 then it is ok:

[{t:"#0f00bf"},"x\nx\n\n\n\n\nx","x"]