line numbers may not be correct for mixed line endings

From IRC chat with Martin [gz].

<mgz> no, but I think you might have to start wondering about what someone wanting the line numbers containing "a" in a file like "\r\r\na\n\r\r\na" should get str.splitlines does (\r\n \n \r) -> \n and text mode does (\r\n \n) -> \n but bzr doesn't help you out at all (in a default setup at any rate) and the regexp engine doesn't like unexpected \r