StructTraits to map mus::mojom::Event to unique_ptr<ui::Event>

components/mus/ws/window_tree.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/mus/ws/window_tree.h"
 
 #include <stddef.h>
 
 #include <utility>
 
@@ skipping 381 matching lines @@
     host->AddActivationParent(window);
 }
 
 void WindowTree::OnChangeCompleted(uint32_t change_id, bool success) {
   client()->OnChangeCompleted(change_id, success);
 }
 
 void WindowTree::OnAccelerator(uint32_t accelerator_id,
                                const ui::Event& event) {
   DCHECK(window_manager_internal_);
+  // TODO(moshayedi): crbug.com/617167. Don't clone even once we map
+  // mojom::Event directly to ui::Event.
   window_manager_internal_->OnAccelerator(accelerator_id,
-                                          mojom::Event::From(event));
+                                          ui::Event::Clone(event));
 }
 
 void WindowTree::ClientJankinessChanged(WindowTree* tree) {
   tree->janky_ = !tree->janky_;
   if (window_manager_internal_) {
     window_manager_internal_->WmClientJankinessChanged(
         tree->id(), tree->janky());
   }
 }
 
@@ skipping 543 matching lines @@
   // randomly.
   // TODO(moshayedi): Find a faster way to generate ids.
   event_ack_id_ = 0x1000000 | (rand() & 0xffffff);
   event_source_wms_ = GetWindowManagerState(target);
   // Should only get events from windows attached to a host.
   DCHECK(event_source_wms_);
   bool matched_observer =
       event_observer_matcher_ && event_observer_matcher_->MatchesEvent(event);
   client()->OnWindowInputEvent(
       event_ack_id_, ClientWindowIdForWindow(target).id,
-      mojom::Event::From(event), matched_observer ? event_observer_id_ : 0);
+      ui::Event::Clone(event), matched_observer ? event_observer_id_ : 0);
 }
 
 void WindowTree::SendToEventObserver(const ui::Event& event) {
   if (event_observer_matcher_ && event_observer_matcher_->MatchesEvent(event))
-    client()->OnEventObserved(mojom::Event::From(event), event_observer_id_);
+    client()->OnEventObserved(ui::Event::Clone(event), event_observer_id_);
 }
 
 void WindowTree::NewWindow(
     uint32_t change_id,
     Id transport_window_id,
     mojo::Map<mojo::String, mojo::Array<uint8_t>> transport_properties) {
   std::map<std::string, std::vector<uint8_t>> properties;
   if (!transport_properties.is_null()) {
     properties =
         transport_properties.To<std::map<std::string, std::vector<uint8_t>>>();
@@ skipping 515 matching lines @@
 }
 
 bool WindowTree::IsWindowRootOfAnotherTreeForAccessPolicy(
     const ServerWindow* window) const {
   WindowTree* tree = window_server_->GetTreeWithRoot(window);
   return tree && tree != this;
 }
 
 }  // namespace ws
 }  // namespace mus