OSDWindow::resize(const FbTk::BiDiString&) shadowed FbWindow::resize(x, y). To
fix this I renamed the function to OSDWindow::resizeForText() to make the
intention clear.
a 'BidiString' holds both the logical content and the visual reordered
version of the content of a string. this helps to reduce the number of
calls to reorder the string before drawing it (as introduced in the patch
from Ken Bloom) and to be more consistent in menus and textboxes (drawing
cursors and underlining text).
