Fix small regressions in GtkNotebook tab detaching. Bug #378852.

Fix small regressions in GtkNotebook tab detaching. Bug #378852.

2006-12-26  Carlos Garnacho  <carlosg@gnome.org>

        Fix small regressions in GtkNotebook tab detaching. Bug #378852.

        * gtk/gtknotebook.c (gtk_notebook_do_arrow): grab focus to allow tabs
        scrolling when hovering with a detached tab.
        (gtk_notebook_stop_reorder): Do not deparent the wrong tab if the
        focus tab has changed during a tab DND operation.
        (gtk_notebook_drag_end): ensure that the dropped tab gets focused.
        (gtk_notebook_paint): do not take cur_page as a reference to paint the
        box if it's detached.
        (gtk_notebook_calculate_tabs_allocation): focus_tab may be different
        to the detached tab if we hover the arrows during a tabs detaching
        operation, do not allocate it unconditionally in 0,0.