After a frustrating couple of hours fooling with this, I finally found a way to end it. I also tried removing the battery and all else I could think of. Been searching everywhere online, still have no idea what it is, what it was downloading or why. But, I don't care...it's gone. and Facebook seems to be working well.
I have a Samsung Epic 4g Sprint android phone.
I went to downloads and found it under "other" downloads. I clicked on the other download button. But, again could not figure out what to do. I finally just pushed my finger on the download green line and held it there until it turned blue. check marked in the box and pushed the clear button. It went away. I've been checking my phone constantly for the past half our and it has not returned.
Hope this helps a little! Good Luck!!
LindaJ