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

ui/aura/window_event_dispatcher_delegate.h

Index: ui/aura/window_event_dispatcher_delegate.h
diff --git a/ui/aura/window_event_dispatcher_delegate.h b/ui/aura/window_event_dispatcher_delegate.h
new file mode 100644
index 0000000000000000000000000000000000000000..992099d9f41fde8e82b32317ea5bd2620d03e57e
--- /dev/null
+++ b/ui/aura/window_event_dispatcher_delegate.h
@@ -0,0 +1,45 @@
+// Copyright (c) 2016 The Chromium Authors. All rights reserved.

[sadrul, 2016/05/31 16:36:32]

We don't do (c) no more

[Mark Dittmer, 2016/05/31 17:05:42]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef UI_AURA_WINDOW_EVENT_DISPATCHER_DELEGATE_H_
+#define UI_AURA_WINDOW_EVENT_DISPATCHER_DELEGATE_H_
+
+#include <stdint.h>
+
+#include "base/macros.h"
+#include "ui/aura/aura_export.h"
+
+namespace gfx {
+class Point;
+}
+
+namespace ui {
+class MouseEvent;
+class TouchEvent;
+}
+
+namespace aura {
+
+class Window;
+
+class AURA_EXPORT WindowEventDispatcherDelegate {
+ public:
+  WindowEventDispatcherDelegate() {}
+  ~WindowEventDispatcherDelegate() {}
+
+  void SetLastMouseLocation(const Window* root_window,
+                            const gfx::Point& location_in_root) const;
+  gfx::Point GetLastMouseLocationInRoot(const Window* window) const;
+  bool IsMouseButtonDown() const;

[sadrul, 2016/05/31 16:36:32]

I don't think this should have any of the getters. Its responsibility would be
to update the state in Env. The rest of the code that currently reads the state
from Env should continue to do so.

[Mark Dittmer, 2016/05/31 17:05:42]

Done.

+  void PreDispatchMouseEvent(ui::MouseEvent* event) const;
+  void PreDispatchTouchEvent(ui::TouchEvent* event, uint32_t touch_ids_down)
+      const;
+
+private:
+  DISALLOW_COPY_AND_ASSIGN(WindowEventDispatcherDelegate);
+};
+
+}  // namespace aura
+
+#endif  // UI_AURA_WINDOW_EVENT_DISPATCHER_DELEGATE_H_