mus: Implement Window Server Capture

components/mus/ws/display_manager.cc

Index: components/mus/ws/display_manager.cc
diff --git a/components/mus/ws/display_manager.cc b/components/mus/ws/display_manager.cc
index 205a650638f277782faf588fb3f4fb7b76097c0a..aa39c76d1788d8cdbbd05f1790ecbc7776d488e2 100644
--- a/components/mus/ws/display_manager.cc
+++ b/components/mus/ws/display_manager.cc
@@ -237,6 +237,14 @@ void DefaultDisplayManager::SetTitle(const base::string16& title) {
   platform_window_->SetTitle(title);
 }
 
+void DefaultDisplayManager::SetCapture() {
+  platform_window_->SetCapture();
+}
+
+void DefaultDisplayManager::ReleaseCapture() {
+  platform_window_->ReleaseCapture();
+}
+
 void DefaultDisplayManager::SetCursorById(int32_t cursor_id) {
 #if !defined(OS_ANDROID)
   // TODO(erg): This still isn't sufficient, and will only use native cursors
@@ -404,7 +412,9 @@ void DefaultDisplayManager::OnClosed() {
 void DefaultDisplayManager::OnWindowStateChanged(
     ui::PlatformWindowState new_state) {}
 
-void DefaultDisplayManager::OnLostCapture() {}
+void DefaultDisplayManager::OnLostCapture() {
+  delegate_->OnLostCapture();
+}
 
 void DefaultDisplayManager::OnAcceleratedWidgetAvailable(
     gfx::AcceleratedWidget widget,