Preserve cursor position

[bracadabra]

Prevent reset of cursor position after password visibility changes

[behelit]

I may have copied your changes incorrectly but this seems to put the cursor to the end after toggling?
It's better than the previous implementation where it goes all over the place, but it doesn't seem to be preserving the cursor location?

[bracadabra]

@behelit The problem linked with touch area of compound drawable. Cursor move to the end bacause you click on EditText, not drawable. You can enlarge touch bounds like this:

touchSlop = ViewConfiguration.get(getContext()).getScaledTouchSlop();

if (event.getAction() == MotionEvent.ACTION_DOWN
                && event.getX() >= (getRight() - getCompoundDrawables()[2].getBounds().width()
                - touchSlop))

[lisawray]

Thanks for the pull request! I'm closing it because I used a similar approach but preserved both selection start and end.

#17