Fixed crash on mixed use of keyboard and mouse for Fl_Menu_Button (STR #1356)

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.1@5259 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

CHANGES

@@ -1,5 +1,7 @@
 CHANGES IN FLTK 1.1.8
 
+	- Fixed crash on mixed use of keyboard and mouse for
+	  Fl_Menu_Button (STR #1356)
 	- Fixed Fl_Window::visible() and shown() for OS X
 	  (STR #1341)
 	- Fixed Fl_Window::copy_label() losing copy (STR #1332)

src/Fl_Menu.cxx

@@ -533,6 +533,9 @@ static void setitem(int m, int n) {
 
 static int forward(int menu) { // go to next item in menu menu if possible
   menustate &pp = *p;
+  // Fl_Menu_Button can geberate menu=-1. This line fixes it and selectes the first item.
+  if (menu==-1) 
+    menu = 0;
   menuwindow &m = *(pp.p[menu]);
   int item = (menu == pp.menu_number) ? pp.item_number : m.selected;
   while (++item < m.numitems) {