mus Window Server: implement event capture

components/mus/ws/window_tree_impl.cc

Index: components/mus/ws/window_tree_impl.cc
diff --git a/components/mus/ws/window_tree_impl.cc b/components/mus/ws/window_tree_impl.cc
index 4cdce9d6db16c866092bb502d92b33cf36e8e820..df73c46fbc683ac2ef8f7fb5b828a34bf57b2363 100644
--- a/components/mus/ws/window_tree_impl.cc
+++ b/components/mus/ws/window_tree_impl.cc
@@ -607,6 +607,17 @@ bool WindowTreeImpl::ShouldRouteToWindowManager(
   return is_wm ? false : true;
 }
 
+void WindowTreeImpl::ProcessLostCapture(const ServerWindow* old_capture_window,
+                                        bool originated_change) {
+  if ((originated_change &&
+       connection_manager_->current_operation_type() ==
+           OperationType::RELEASE_CAPTURE) ||
+      !IsWindowKnown(old_capture_window)) {
+    return;
+  }
+  client()->OnLostCapture(WindowIdToTransportId(old_capture_window->id()));
+}
+
 ClientWindowId WindowTreeImpl::ClientWindowIdForWindow(
     const ServerWindow* window) const {
   auto iter = window_id_to_client_id_map_.find(window->id());
@@ -995,6 +1006,38 @@ void WindowTreeImpl::GetWindowTree(
   callback.Run(WindowsToWindowDatas(windows));
 }
 
+void WindowTreeImpl::SetCapture(uint32_t change_id, Id window_id) {
+  ServerWindow* window = GetWindowByClientId(ClientWindowId(window_id));
+  WindowTreeHostImpl* host = GetHost(window);
+  ServerWindow* current_capture_window =
+      host ? host->GetCaptureWindow() : nullptr;
+  bool success = window && access_policy_->CanSetCapture(window) && host &&
+                 (!current_capture_window ||
+                  access_policy_->CanSetCapture(current_capture_window)) &&
+                 event_ack_id_;
+  if (success) {
+    Operation op(this, connection_manager_, OperationType::SET_CAPTURE);
+    host->SetCapture(window, !HasRoot(window));
+  }
+  client_->OnChangeCompleted(change_id, success);
+}
+
+void WindowTreeImpl::ReleaseCapture(uint32_t change_id, Id window_id) {
+  ServerWindow* window = GetWindowByClientId(ClientWindowId(window_id));
+  WindowTreeHostImpl* host = GetHost(window);
+  ServerWindow* current_capture_window =
+      host ? host->GetCaptureWindow() : nullptr;
+  bool success = window && host &&
+                 (!current_capture_window ||
+                  access_policy_->CanSetCapture(current_capture_window)) &&
+                 window == current_capture_window;
+  if (success) {
+    Operation op(this, connection_manager_, OperationType::RELEASE_CAPTURE);
+    host->SetCapture(nullptr, false);
+  }
+  client_->OnChangeCompleted(change_id, success);
+}
+
 void WindowTreeImpl::SetWindowBounds(uint32_t change_id,
                                      Id window_id,
                                      mojo::RectPtr bounds) {