Given the spread of the device APIs that Mozilla was forced to develop for Firefox OS, I think it is clear that Firefox OS has already done more for Mozilla's mission than maintaining the previous embeddings ever could.
"Our mission is to promote openness, innovation & opportunity on the Web."
It's not clear to me that FireFox OS has done anything for Mozilla's mission. Indeed, the Firefox OS home page seems to indicate Firefox's goal is to provide carriers and OEMs with an alternative to Android, and help them maintain customer relationships. WTF? Open source vendor lockin?
I think Mozilla's announcement makes their reasoning fairly clear:
https://groups.google.com/forum/#!topic/mozilla.dev.embeddin...
My summary is:
- The old embedding infrastructure was difficult to use and expensive to maintain
- It was also a technical dead end
- Better embedding infrastructure depended on complex architectural changes to Firefox
- Firefox is Mozilla's bread-and-butter, in terms of visibility, influence and revenue
- Mozilla has ambitious goals and does not have infinite resources
Forget for a moment that we're talking about Mozilla, Firefox and Gecko embedding. In a different context, what would you do?