Fixed pulldown menu position when at the bottom of the screen (STR #2880).

CHANGES.txt

@@ -145,6 +145,7 @@ Changes in FLTK 1.4.0					Released: ??? ?? 2019
   Bug Fixes
 
   - (add new items here)
+  - Fixed pulldown menu position when at the bottom of the screen (STR #2880).
   - Fixed missing item handling in Fl_Chekc_Browser (STR #3480).
   - Fixed Delete key in Fl_Input deleting entire widgets in Fluid (STR #2841).
   - Reorganized Fluid Template feature (STR #3336).

src/Fl_Menu.cxx

@@ -400,6 +400,13 @@ menuwindow::menuwindow(const Fl_Menu_Item* m, int X, int Y, int Wp, int Hp,
         // draw the menu to the right
         Y = Y-h()+itemheight+Fl::box_dy(box());
       }
+      if (t) {
+        if (menubar_title) {
+          Y = Y + Fl::menu_linespacing() - Fl::box_dw(button->box());
+        } else {
+          Y += 2*Htitle+2*BW+3;
+        }
+      }
     }
   }
   if (m) y(Y); else {y(Y-2); w(1); h(1);}