Js, Hl, Cpp and Jvm pass.

Eval, Php and Python fail with this:

    line: 61, expected -1 but it is 0
    line: 62, expected -1 but it is 1
    line: 63, expected -1 but it is 3
    line: 64, expected -1 but it is 4
    line: 65, expected -1 but it is 5

Neko fails with those plus one more:

    line: 66, expected -1 but it is 6

Lua fails like neko plus one more (which is already tracked in #11567):

    line: 60, expected 6 but it is 0

I have fixed Eval and the implementation on UnicodeString. This is a specification change, but I doubt that anyone relied on this behavior there was a disconnect between UnicodeString and non-UnicodeString already anyway, so it"s good to clean that up.

Fixed python and neko as well. I don"t have local php and lua installations, but I"ll attempt a blind fix on PHP at least.

Documenting this crap is harder than implementing it... I hope I got all the intricacies right now. This whole special situation with "" is very silly.