aura: Introduce EventInjector.

ui/aura/event_injector.cc

+// Copyright 2017 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 "ui/aura/event_injector.h"
+
+#include "services/service_manager/public/cpp/connector.h"
+#include "services/ui/public/interfaces/constants.mojom.h"
+#include "ui/aura/env.h"
+#include "ui/aura/mus/window_tree_client.h"
+#include "ui/aura/window_tree_host.h"
+#include "ui/display/display.h"
+#include "ui/display/screen.h"
+#include "ui/events/event.h"
+#include "ui/events/event_sink.h"
+
+namespace {
+std::unique_ptr<ui::Event> MapEvent(const ui::Event& event) {
+  if (event.IsScrollEvent()) {
+    return base::MakeUnique<ui::PointerEvent>(
+        ui::MouseWheelEvent(*event.AsScrollEvent()));
+  }
+
+  if (event.IsMouseEvent())
+    return base::MakeUnique<ui::PointerEvent>(*event.AsMouseEvent());
+
+  if (event.IsTouchEvent())
+    return base::MakeUnique<ui::PointerEvent>(*event.AsTouchEvent());
+
+  return ui::Event::Clone(event);
+}
+
+}  // namespace
+
+namespace aura {
+
+EventInjector::EventInjector() {}
+
+EventInjector::~EventInjector() {}
+
+ui::EventDispatchDetails EventInjector::Inject(WindowTreeHost* host,
+                                               ui::Event* event) {
+  Env* env = Env::GetInstance();
+  DCHECK(env);
+  DCHECK(host);
+  DCHECK(event);
+
+  if (env->mode() == Env::Mode::LOCAL)
+    return host->event_sink()->OnEventFromSource(event);
+  if (!window_server_ptr_) {
+    env->window_tree_client_->connector()->BindInterface(
+        ui::mojom::kServiceName, &window_server_ptr_);
+  }
+  display::Screen* screen = display::Screen::GetScreen();
+  window_server_ptr_->DispatchEvent(
+      screen->GetDisplayNearestWindow(host->window()).id(), MapEvent(*event),
+      base::Bind([](bool result) { DCHECK(result); }));
+  return ui::EventDispatchDetails();
+}
+
+}  // namespace aura