tests: Fix window centering test with Wayland display scaling mode

The usable fullscreen bounds need to be queried after window creation, as Wayland can send different usable bounds depending on the focused window's scaling mode.

test/testautomation_video.c

@@ -1750,7 +1750,7 @@ static int video_setWindowCenteredOnDisplay(void *arg)
                 int expectedX = 0, expectedY = 0;
                 int currentDisplay;
                 int expectedDisplay;
-                SDL_Rect expectedDisplayRect;
+                SDL_Rect expectedDisplayRect, expectedFullscreenRect;
                 SDL_PropertiesID props;
 
                 /* xVariation is the display we start on */
@@ -1826,16 +1826,24 @@ static int video_setWindowCenteredOnDisplay(void *arg)
                 SDL_GetWindowSize(window, &currentW, &currentH);
                 SDL_GetWindowPosition(window, &currentX, &currentY);
 
+                /* Get the expected fullscreen rect.
+                 * This needs to be queried after window creation and positioning as some drivers can alter the
+                 * usable bounds based on the window scaling mode.
+                 */
+                result = SDL_GetDisplayBounds(expectedDisplay, &expectedFullscreenRect);
+                SDLTest_AssertPass("SDL_GetDisplayBounds()");
+                SDLTest_AssertCheck(result == 0, "Verify return value; expected: 0, got: %d", result);
+
                 if (!video_driver_is_wayland) {
                     SDLTest_AssertCheck(currentDisplay == expectedDisplay, "Validate display ID (current: %d, expected: %d)", currentDisplay, expectedDisplay);
                 } else {
                     SDLTest_Log("Skipping display ID validation: Wayland driver does not support window positioning");
                 }
-                SDLTest_AssertCheck(currentW == expectedDisplayRect.w, "Validate width (current: %d, expected: %d)", currentW, expectedDisplayRect.w);
-                SDLTest_AssertCheck(currentH == expectedDisplayRect.h, "Validate height (current: %d, expected: %d)", currentH, expectedDisplayRect.h);
+                SDLTest_AssertCheck(currentW == expectedFullscreenRect.w, "Validate width (current: %d, expected: %d)", currentW, expectedFullscreenRect.w);
+                SDLTest_AssertCheck(currentH == expectedFullscreenRect.h, "Validate height (current: %d, expected: %d)", currentH, expectedFullscreenRect.h);
                 if (!video_driver_is_wayland) {
-                    SDLTest_AssertCheck(currentX == expectedDisplayRect.x, "Validate x (current: %d, expected: %d)", currentX, expectedDisplayRect.x);
-                    SDLTest_AssertCheck(currentY == expectedDisplayRect.y, "Validate y (current: %d, expected: %d)", currentY, expectedDisplayRect.y);
+                    SDLTest_AssertCheck(currentX == expectedFullscreenRect.x, "Validate x (current: %d, expected: %d)", currentX, expectedFullscreenRect.x);
+                    SDLTest_AssertCheck(currentY == expectedFullscreenRect.y, "Validate y (current: %d, expected: %d)", currentY, expectedFullscreenRect.y);
                 } else {
                     SDLTest_Log("Skipping window position validation: Wayland driver does not support window positioning");
                 }