Revert: 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 492bad06abb5038984d5eb5fcfc3c1c5a8e3ecba..c6d4ee1bf65a765a2a6969b50d27d911bef10439 100644
--- a/services/ui/ws/window_server_test_base.cc
+++ b/services/ui/ws/window_server_test_base.cc
@@ -143,6 +143,10 @@
 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_;
 }