We're not even close to that yet, some articles around the internetz hinting that it's possible doesn't make it so.
If it's ever done & done well, it needs to be fully supported by Jolla or someone else fully ensconced in the "sailfish ecosystem".
If we're lucky Jolla/Other may help smooth the way for 1 or more of the most popular Android handsets...
But I'd wager that'll be long after the 1st Sailfish phone has had time to settle on the market, if it ever happens.
Maybe big communities like xda-dev etc. + the maemo/meego one will start to run away with the concept, & get close to delivering something polished.
It looks like Jolla is starting to facilitate that side of things a bit more at least....