OnBootDrive used the "drives" member std::vector for drive paths, but
since PR #4363, this vector is not populated anymore, so we were
accessing it out of bounds.
Actually, drives was not needed in the first place, since we can
get the wxMenu from the event, and from there, get the label directly.
Gets rid of more menu-related code from CodeWindow and puts it back in
CFrame where it belongs.
This turns the previous menu update function within CodeWindow into one
that simply updates the debugger font for its managed controls. It also
improves how the font is actually updated. Previously, fonts would change,
however this wouldn't actually reflect onto the respective controls until
a refresh or update event occurred. Since codeview, callstack, symbols,
callers, and calls windows are all managed by a wxAuiManager instance,
calling Update() on it after the font has been set will reflect font
changes immediately.
On Linux, the FindFocus method from wx simply doesn't work, it would on some environment report that dolphin has the focus while it doesn't have it. This is why an alternative method has to be used which is to set a focus flag whenever the render frame gets activated.