Fix flickering of all animation and haloes.

There was an erronous call left to display::flip() that caused the
flickering. The fix is simply to remove the function and the call to
it.

src/display.cpp

@@ -1399,13 +1399,6 @@ void display::toggle_debug_foreground()
 	debug_foreground = !debug_foreground;
 }
 
-void display::flip()
-{
-
-	video().flip();
-
-}
-
 void display::post_draw() {
 	if(video().faked()) {
 			return;
@@ -1465,10 +1458,8 @@ void display::update_display()
 	} else if(fps_handle_ != 0) {
 		clear_fps_label();
 	}
-
-	flip();
-
 }
+
 #ifdef SDL_GPU
 static void draw_panel(surface &target, const theme::panel& panel, std::vector<gui::button>& /*buttons*/)
 #else

src/display.hpp

@@ -484,8 +484,6 @@ class display : public filter_context, public video2::draw_layering
 
 	terrain_builder& get_builder() {return *builder_;}
 
-	void flip();
-
 	/** Copy the backbuffer to the framebuffer. */
 	void update_display();
 

src/game_display.cpp

@@ -263,7 +263,7 @@ void game_display::pre_draw() {
 
 
 void game_display::post_draw() {
-	display::pre_draw();
+	display::post_draw();
 	if (boost::shared_ptr<wb::manager> w = wb_.lock()) {
 		w->post_draw();
 	}