Update source to SDL2 2.0.12

Edward Rudd

2020-05-02 03f8528315fa46c95991a34f3325d7b33ae5538c

 source/src/video/SDL_shape.c

@@ -1,6 +1,6 @@
/*
  Simple DirectMedia Layer
  Copyright (C) 1997-2018 Sam Lantinga <slouken@libsdl.org>
  Copyright (C) 1997-2020 Sam Lantinga <slouken@libsdl.org>

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
@@ -88,7 +88,7 @@
            pixel = (Uint8 *)(shape->pixels) + (y*shape->pitch) + (x*shape->format->BytesPerPixel);
            switch(shape->format->BytesPerPixel) {
                case(1):
                    pixel_value = *(Uint8*)pixel;
                    pixel_value = *pixel;
                    break;
                case(2):
                    pixel_value = *(Uint16*)pixel;
@@ -141,7 +141,7 @@
            pixel = (Uint8 *)(mask->pixels) + (y*mask->pitch) + (x*mask->format->BytesPerPixel);
            switch(mask->format->BytesPerPixel) {
                case(1):
                    pixel_value = *(Uint8*)pixel;
                    pixel_value = *pixel;
                    break;
                case(2):
                    pixel_value = *(Uint16*)pixel;