Olympus E-M5II has same E-M5 sensor.

Image of the E-M5 sensor by Engadget

Olympus is going the Canon route and will keep "re-using" the same sensor on the newer generation cameras. The E-M5II will get the same E-M5 sensor without PDAF.

But still, Olympus will add the sensor shift shooting feature that will allow you to take 40 megapixel pictures by combining 8 pictures shot in rapid succession.

from Mirrorless Rumors