Introduce aura::Env controller to abstract away changes to aura::Env

ui/aura/env_input_state_controller.cc

+// Copyright 2016 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/env_input_state_controller.h"
+
+#include "ui/aura/client/screen_position_client.h"
+#include "ui/aura/env.h"
+#include "ui/events/event.h"
+#include "ui/gfx/geometry/point.h"
+
+namespace aura {
+
+void EnvInputStateController::UpdateStateForMouseEvent(
+    const Window* window, ui::MouseEvent* event) const {
+  switch (event->type()) {
+    case ui::ET_MOUSE_PRESSED:
+      Env::GetInstance()->set_mouse_button_flags(event->button_flags());
+      break;
+    case ui::ET_MOUSE_RELEASED:
+      Env::GetInstance()->set_mouse_button_flags(
+          event->button_flags() & ~event->changed_button_flags());
+      break;
+    default:
+      break;
+  }
+
+  if (!(event->flags() & ui::EF_IS_SYNTHESIZED))
+    SetLastMouseLocation(window, event->root_location());
+}
+
+void EnvInputStateController::UpdateStateForTouchEvent(ui::TouchEvent* event) {
+
+  switch (event->type()) {
+    case ui::ET_TOUCH_PRESSED:
+      touch_ids_down_ |= (1 << event->touch_id());
+      Env::GetInstance()->set_touch_down(touch_ids_down_ != 0);
+      break;
+
+      // Handle ET_TOUCH_CANCELLED only if it has a native event.
+    case ui::ET_TOUCH_CANCELLED:
+      if (!event->HasNativeEvent())
+        break;
+      // fallthrough
+    case ui::ET_TOUCH_RELEASED:
+      touch_ids_down_ = (touch_ids_down_ | (1 << event->touch_id())) ^
+          (1 << event->touch_id());
+      Env::GetInstance()->set_touch_down(touch_ids_down_ != 0);
+      break;
+
+    case ui::ET_TOUCH_MOVED:
+      break;
+
+    default:
+      NOTREACHED();
+      break;
+  }
+}
+
+void EnvInputStateController::SetLastMouseLocation(
+    const Window* root_window, const gfx::Point& location_in_root) const {
+  client::ScreenPositionClient* client =
+      client::GetScreenPositionClient(root_window);
+  if (client) {
+    gfx::Point location_in_screen = location_in_root;
+    client->ConvertPointToScreen(root_window, &location_in_screen);
+    Env::GetInstance()->set_last_mouse_location(location_in_screen);
+  } else {
+    Env::GetInstance()->set_last_mouse_location(location_in_root);
+  }
+}
+
+}  // namespace aura