Adds ability for accelerators to add key/value pairs to KeyEvent

services/ui/ws/window_manager_state.cc

Index: services/ui/ws/window_manager_state.cc
diff --git a/services/ui/ws/window_manager_state.cc b/services/ui/ws/window_manager_state.cc
index d9b9ed52c760fc9feb2932ce2b94462aeabe3a55..4b03ed4f4499ea14526285a6db1e2258660cc1af 100644
--- a/services/ui/ws/window_manager_state.cc
+++ b/services/ui/ws/window_manager_state.cc
@@ -298,7 +298,9 @@ void WindowManagerState::OnEventAck(mojom::WindowTree* tree,
   ProcessNextEventFromQueue();
 }
 
-void WindowManagerState::OnAcceleratorAck(mojom::EventResult result) {
+void WindowManagerState::OnAcceleratorAck(
+    mojom::EventResult result,
+    const std::unordered_map<std::string, std::vector<uint8_t>>& properties) {
   if (!in_flight_event_details_ ||
       in_flight_event_details_->phase !=
           EventDispatchPhase::PRE_TARGET_ACCELERATOR) {
@@ -311,6 +313,9 @@ void WindowManagerState::OnAcceleratorAck(mojom::EventResult result) {
       std::move(in_flight_event_details_);
 
   if (result == mojom::EventResult::UNHANDLED) {
+    DCHECK(details->event->IsKeyEvent());
+    if (!properties.empty())
+      details->event->AsKeyEvent()->SetProperties(properties);
     event_processing_display_id_ = details->display_id;
     event_dispatcher_.ProcessEvent(
         *details->event, EventDispatcher::AcceleratorMatchPhase::POST_ONLY);
@@ -381,7 +386,7 @@ void WindowManagerState::OnEventAckTimeout(ClientSpecificId client_id) {
     window_tree_->ClientJankinessChanged(hung_tree);
   if (in_flight_event_details_->phase ==
       EventDispatchPhase::PRE_TARGET_ACCELERATOR) {
-    OnAcceleratorAck(mojom::EventResult::UNHANDLED);
+    OnAcceleratorAck(mojom::EventResult::UNHANDLED, KeyEvent::Properties());
   } else {
     OnEventAck(
         in_flight_event_details_ ? in_flight_event_details_->tree : nullptr,