Remove calls to empty update_whole_screen() function

The function's contents were SDL1.2 only, and it now does nothing in
SDL2.

src/events.cpp

@@ -413,10 +413,6 @@ void pump()
 						cursor::set_focus(1);
 						break;
 
-					case SDL_WINDOWEVENT_EXPOSED:
-						update_whole_screen();
-						break;
-
 					case SDL_WINDOWEVENT_RESIZED:
 						info.resize_dimensions.first = event.window.data1;
 						info.resize_dimensions.second = event.window.data2;

src/game_initialization/multiplayer_ui.cpp

@@ -286,8 +286,6 @@ void ui::draw_contents()
 	if(background == NULL)
 		return;
 	sdl_blit(background, NULL, video().getSurface(), NULL);
-	update_whole_screen();
-
 	hide_children(false);
 }
 

src/intro.cpp

@@ -41,7 +41,6 @@ void the_end(CVideo &video, std::string text, unsigned int duration)
 	SDL_Rect area = screen_area();
 	sdl::fill_rect(video.getSurface(),&area,0);
 
-	update_whole_screen();
 	video.flip();
 
 	const size_t font_size = font::SIZE_XLARGE;

src/loadscreen.cpp

@@ -302,7 +302,6 @@ void loadscreen::clear_screen()
 	surface& disp(screen_.getSurface());      // Screen surface.
 	// Make everything black.
 	sdl::fill_rect(disp,&area,SDL_MapRGB(disp->format,0,0,0));
-	update_whole_screen();
 	screen_.flip();
 #endif
 }

src/storyscreen/render.cpp

@@ -355,7 +355,6 @@ bool part_ui::render_floating_images()
 	return true;
 #else
 	events::raise_draw_event();
-	update_whole_screen();
 
 	skip_ = false;
 	last_key_ = true;
@@ -750,7 +749,6 @@ void part_ui::render_story_box()
 
 	const std::string& storytxt = p_.text();
 	if(storytxt.empty()) {
-		update_whole_screen();
 		wait_for_input();
 		return;
 	}
@@ -858,9 +856,7 @@ void part_ui::render_story_box()
 		}
 
 		if (dirty_ || first) {
-			if(imgs_.empty()) {
-				update_whole_screen();
-			} else if(update_area.h > 0) {
+			if(!imgs_.empty() && update_area.h > 0) {
 				update_rect(update_area);
 			}
 		}

src/video.cpp

@@ -204,11 +204,6 @@ void update_rect(const SDL_Rect& rect_value)
 	}
 }
 
-void update_whole_screen()
-{
-}
-
-
 void CVideo::video_event_handler::handle_window_event(const SDL_Event &event)
 {
 	if (event.type == SDL_WINDOWEVENT) {

src/video.hpp

@@ -55,7 +55,6 @@ SDL_Rect screen_area();
 //which areas of the screen will be updated when the buffer is flipped?
 void update_rect(size_t x, size_t y, size_t w, size_t h);
 void update_rect(const SDL_Rect& rect);
-void update_whole_screen();
 
 class CVideo : private boost::noncopyable {
 public: