fix #10581: getTile byte-ordering issue (rebased onto dev_4_4)

This is a rebase of gh-1759 but as `BfPixelBuffer.java` was different on the two branches and so 4b33351 in this PR differs from its equivalent commit in gh-1759, 65995c6. The tests in this PR pass but this difference probably needs reviewing more.

--rebased-from #1759