Brush pane tweaks

Detail:
  Hide the scrollbar under the brushes if the pane is narrow enough to show all.
  Remove excess space after interactive help token.

c/ToolWindow

@@ -1063,6 +1063,8 @@ static void make_brush_pane (void)
 { char *brush_name;
   int num_sys_brushes = 0;
   main_sprite *sprite_ptr;
+  int panewidth, max_brush_index;
+  wimp_box last_bbox;
 
   ftracef0 ("make_brush_pane\n");
 
@@ -1085,6 +1087,7 @@ static void make_brush_pane (void)
     if (sprite_ptr == NULL)
       break;
   }
+  max_brush_index = num_brushpane_icons;
 
   /* Add the last user brush, if any. Mustn't have duplicates *
    * or invalid characters! */
@@ -1102,6 +1105,16 @@ static void make_brush_pane (void)
   if (tools_brushpane_handle != 0)
     destroy_brush_pane ();
 
+  /* As the number of brushes is fixed when there's a user brush, we don't
+     want a scroll bar if they all fit on the screen */
+  get_brush_pane_icon_bbox (max_brush_index, &last_bbox);
+  panewidth = tools_brushpane_template.t.box.x1 - tools_brushpane_template.t.box.x0;
+  if (last_bbox.x0 >= 0 && last_bbox.x0 <  panewidth &&
+      last_bbox.x1 >  0 && last_bbox.x1 <= panewidth)
+    tools_brushpane_template.t.flags &= ~wimp_WHSCR;
+  else
+    tools_brushpane_template.t.flags |= wimp_WHSCR;
+
   ftracef0 ("Create brushes window pane\n");
   if (main_create_window (&tools_brushpane_template.t, &tools_brushpane_handle,
                           &brush_pane_event_handler, NULL) == 0)