Reset cursors when Scintilla widget is realized.
Reset cursors when Scintilla widget is realized.

Solves problem which occurs when Scintilla widget is unrealized and then
re-realized and the cursor is left at GDK_XTERM even over the scrollbars.
When the Scintilla widget is unrealized it's GdkWindows are destroyed and
so the previous cursors are lost.  This commit forces default cursors on
the text and scrollbar windows when the widget is realized.

References:
http:fe5217da1b6645a9ae79189250c5dc6c374f4112@lyra.org/msg01364.html
http://git.geany.org/geany/tree/plugins/splitwindow.c#n310
http:e37e5a9dc379442cbfeef1aec7a0fe54173467e9@uvena.de/msg00821.html

R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone