Remove WindowTreeClientDelegate::GetCaptureClient() and WindowTreeClient::GetCaptureClient().

services/ui/ws/window_server_test_base.cc

Index: services/ui/ws/window_server_test_base.cc
diff --git a/services/ui/ws/window_server_test_base.cc b/services/ui/ws/window_server_test_base.cc
index c6d4ee1bf65a765a2a6969b50d27d911bef10439..492bad06abb5038984d5eb5fcfc3c1c5a8e3ecba 100644
--- a/services/ui/ws/window_server_test_base.cc
+++ b/services/ui/ws/window_server_test_base.cc
@@ -143,10 +143,6 @@ void WindowServerTestBase::OnEmbedRootDestroyed(
 void WindowServerTestBase::OnPointerEventObserved(const ui::PointerEvent& event,
                                                   aura::Window* target) {}
 
-aura::client::CaptureClient* WindowServerTestBase::GetCaptureClient() {
-  return wm_state_.capture_controller();
-}
-
 aura::PropertyConverter* WindowServerTestBase::GetPropertyConverter() {
   return &property_converter_;
 }