Make text-combine and font variations play nicely together

• Component: Text
• Status: NEW ---

[Myles C. Maxfield]

text-combine uses ctFont() to apply a font feature to the font, and then uses this new font when performing width calculations to try to squish text inside the text combine. Instead, this mechanism of applying the feature should be unified with the existing font features infrastructure.

When this is complete, the only difference between FontPlatformData::m_font and FontPlatformData::m_ctFont will be the cascade list.