[Shemos 2(19)](http://www.chabad.org/library/bible_cdo/aid/9863#showrashi=true) 

They [*the daughters of Yisro*] replied, "An Egyptian man rescued us from the hand[s] of the shepherds, and he also drew [water] for us and watered the flocks." 

I once heard an interpretation that the Egyptian man was not Moshe himself but the Egyptian that Moshe killed in Egypt [2 (12)] and because of whose death, Moshe had to flee to Midian. 

Who said this interpretation?

(related http://judaism.stackexchange.com/questions/52554/moshe-killing-the-egyptian)