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

ui/aura/env_input_state_controller.cc

Index: ui/aura/env_input_state_controller.cc
diff --git a/ui/aura/env_input_state_controller.cc b/ui/aura/env_input_state_controller.cc
new file mode 100644
index 0000000000000000000000000000000000000000..37ec8d2f85725332ab87496bcd738a29f1d9ef8e
--- /dev/null
+++ b/ui/aura/env_input_state_controller.cc
@@ -0,0 +1,64 @@
+// 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::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);
+  }
+}
+
+gfx::Point EnvInputStateController::GetLastMouseLocationInRoot(
+    const Window* window) const {
+  gfx::Point location = Env::GetInstance()->last_mouse_location();
+  client::ScreenPositionClient* client =
+      client::GetScreenPositionClient(window);
+  if (client)
+    client->ConvertPointFromScreen(window, &location);
+  return location;
+}
+
+void EnvInputStateController::PreDispatchMouseEvent(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;
+  }
+}
+
+void EnvInputStateController::PreDispatchTouchEvent(
+    ui::TouchEvent* event, uint32_t touch_ids_down) const {
+  switch (event->type()) {
+    case ui::ET_TOUCH_PRESSED:
+    case ui::ET_TOUCH_RELEASED:
+      Env::GetInstance()->set_touch_down(touch_ids_down != 0);
+      break;
+    default:
+      break;
+  }
+}
+
+}  // namespace aura