[ft] Rendering regression in 2.8.1 on RGB screens

[Vladimir Panteleev]

Hello,

freetype 2.8.1 seems to have introduced a regression in rendering text 
on RGB screens (most screens are BGR).

When fontconfig is configured as follows:

 <match target="font">
  <edit name="rgba" mode="assign">
   <const>rgb</const>
  </edit>
 </match>

rendering artifacts can be observed in Mozilla Firefox:

2.8: 
https://dump.thecybershadow.net/80a63d8dd78715f6b60614863234316f/Screen%20Shot%202017-10-10%20at%2012.24.54.png

2.8.1: 
https://dump.thecybershadow.net/f0720652b3b31f1457f650b0dece898a/Screen%20Shot%202017-10-10%20at%2012.21.42.png

git bisect points at 410f3799b6a193e20b34c574e6f0f2be2428b1eb ("[smooth] 
Harmony LCD rendering.") as the first bad commit.

--
Best regards,
 Vladimir