Properly set default color scheme.

This fixes a bug where the default color scheme setting doesn't take
effect until the second program run.

Timeline/TLE.fl

@@ -157,6 +157,8 @@ system_colors[ 0 ] = (Fl_Color)Fl::get_color( FL_BACKGROUND_COLOR );
 system_colors[ 1 ] = (Fl_Color)Fl::get_color( FL_FOREGROUND_COLOR  );
 system_colors[ 2 ] = (Fl_Color)Fl::get_color( FL_BACKGROUND2_COLOR  );
 
+set_theme_dark();
+
 // constrain window to size of screen.
 {
         int sx, sy, sw, sh;
@@ -555,11 +557,9 @@ Fl::scheme( Fl::scheme() );}
               }
               MenuItem {} {
                 label Dark
-                callback {Fl::background2( 100, 100, 100 );
-Fl::background( 50, 50, 50 );
-Fl::foreground( 255, 255, 255 );
+                callback {
 
-Fl::scheme( Fl::scheme() );}
+                set_theme_dark(); }
                 xywh {20 20 40 25} type Radio value 1
               }
               MenuItem {} {
@@ -942,6 +942,15 @@ write_line( user_config_dir, "default_path", o->value() );}
   }
 } 
 
+Function {set_theme_dark()} {C return_type void
+} {
+        code { Fl::background2( 100, 100, 100 );
+        Fl::background( 50, 50, 50 );
+        Fl::foreground( 255, 255, 255 );
+
+        Fl::scheme( Fl::scheme() ); } {}
+}
+
 Function {new_project_chooser()} {C return_type void
 } {
   code {New_Project_Dialog nsd;