ui: Cleanup class/struct forward declarations

services/ui/ws/test_server_window_delegate.cc

Index: services/ui/ws/test_server_window_delegate.cc
diff --git a/services/ui/ws/test_server_window_delegate.cc b/services/ui/ws/test_server_window_delegate.cc
index bc232800d77f0346648381ef3a37ce7a12cb8b01..08adb9927efa89fa5d1b6b72553346d3380ac048 100644
--- a/services/ui/ws/test_server_window_delegate.cc
+++ b/services/ui/ws/test_server_window_delegate.cc
@@ -20,10 +20,8 @@ ui::DisplayCompositor* TestServerWindowDelegate::GetDisplayCompositor() {
   return display_compositor_.get();
 }
 
-void TestServerWindowDelegate::OnScheduleWindowPaint(ServerWindow* window) {}
-
-const ServerWindow* TestServerWindowDelegate::GetRootWindow(
-    const ServerWindow* window) const {
+ServerWindow* TestServerWindowDelegate::GetRootWindow(
+    const ServerWindow* window) {
   return root_window_;
 }