SDL: Added patch note for SDL_SetWindowFillDocument()

From a35639c7b53a8ff4b38cbd4ede2128f6cc5da9be Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Mon, 8 Dec 2025 08:18:34 -0800
Subject: [PATCH] Added patch note for SDL_SetWindowFillDocument()

---
 WhatsNew.txt | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/WhatsNew.txt b/WhatsNew.txt
index 42eaa2406d7a5..e085707a5f87b 100644
--- a/WhatsNew.txt
+++ b/WhatsNew.txt
@@ -85,7 +85,8 @@ Linux:
 * Added SDL_PROP_DISPLAY_WAYLAND_WL_OUTPUT_POINTER so you can query the wl_output associated with a display
 
 Emscripten:
-* Added SDL_WINDOW_FILL_DOCUMENT flag for SDL_Windows to take up the whole browser window.
+* Added SDL_WINDOW_FILL_DOCUMENT to indicate that windows expand to fill the whole browser window
+* Added SDL_SetWindowFillDocument() to change whether windows expand to fill the whole browser window
 * Added SDL_PROP_WINDOW_CREATE_EMSCRIPTEN_CANVAS_ID_STRING to allow setting the SDL canvas ID, and SDL_PROP_WINDOW_EMSCRIPTEN_CANVAS_ID_STRING to query it on existing windows
 * Added SDL_PROP_WINDOW_CREATE_EMSCRIPTEN_KEYBOARD_ELEMENT_STRING to specify where keyboard input is bound, and SDL_PROP_WINDOW_EMSCRIPTEN_KEYBOARD_ELEMENT_STRING to query it on existing windows