Christoph Mallon: Replace strlen(x) == 0 (O(n)) by x[0] == '\0' (O(1)).

src/video/windows/SDL_windowsclipboard.c

@@ -137,7 +137,7 @@ WIN_HasClipboardText(_THIS)
     SDL_bool result = SDL_FALSE;
     char *text = WIN_GetClipboardText(_this);
     if (text) {
-        result = (SDL_strlen(text)>0) ? SDL_TRUE : SDL_FALSE;
+        result = text[0] != '\0' ? SDL_TRUE : SDL_FALSE;
         SDL_free(text);
     }
     return result;