Support JavaScript window.moveTo/By() and resizeTo/By() (fixes #698)

Adds new CefDisplayHandler::OnContentsBoundsChange and
CefDisplayHandler::GetRootWindowScreenRect callbacks.

cefclient: Implement the above callbacks and call
CefBrowserHost::NotifyScreenInfoChanged when the root window
bounds change.

cefclient: osr: Use real screen bounds by default. Pass
`--fake-screen-bounds` for the old default behavior.

Load https://tests/window in cefclient for additional
implementation details and usage examples.

tests/cefclient/browser/util_mac.h

@@ -0,0 +1,23 @@
+// Copyright (c) 2025 The Chromium Embedded Framework Authors. All rights
+// reserved. Use of this source code is governed by a BSD-style license that
+// can be found in the LICENSE file.
+
+#ifndef CEF_TESTS_CEFCLIENT_BROWSER_UTIL_MAC_H_
+#define CEF_TESTS_CEFCLIENT_BROWSER_UTIL_MAC_H_
+#pragma once
+
+#include <optional>
+
+#include <Cocoa/Cocoa.h>
+
+#include "include/internal/cef_types_wrappers.h"
+
+namespace client {
+
+// Returns the current DIP screen bounds for a visible window in the restored
+// position, or nullopt if the window is currently minimized or fullscreen.
+std::optional<CefRect> GetWindowBoundsInScreen(NSWindow* window);
+
+}  // namespace client
+
+#endif  // CEF_TESTS_CEFCLIENT_BROWSER_UTIL_MAC_H_