Makes WindowTreeHostMus supply properties directly to window creation

ui/aura/mus/window_tree_host_mus.h

 // Copyright 2015 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.
 
 #ifndef UI_AURA_MUS_WINDOW_TREE_HOST_MUS_H_
 #define UI_AURA_MUS_WINDOW_TREE_HOST_MUS_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 12 matching lines @@
 
 namespace aura {
 
 class InputMethodMus;
 class WindowPortMus;
 class WindowTreeClient;
 class WindowTreeHostMusDelegate;
 
 class AURA_EXPORT WindowTreeHostMus : public aura::WindowTreeHostPlatform {
  public:
+  // |properties| are applied to the window created by this class (using
+  // PropertyConverter).
+  // TODO: this should take an unordered_map, see http://crbug.com/670515.
   WindowTreeHostMus(
       std::unique_ptr<WindowPortMus> window_port,
       WindowTreeClient* window_tree_client,
       int64_t display_id,
       const std::map<std::string, std::vector<uint8_t>>* properties = nullptr);
+
+  // This constructor is intended for creating top level windows in
+  // non-window-manager code. |properties| are properties passed verbatim to
+  // the server, that is, no conversion is done before sending |properties| to
+  // the server. Additionally |properties| are passed to PropertyConverter and
+  // any known properties are set on the Window created by this class.
+  // TODO: this should take an unordered_map, see http://crbug.com/670515.
   explicit WindowTreeHostMus(
       WindowTreeClient* window_tree_client,
       const std::map<std::string, std::vector<uint8_t>>* properties = nullptr);
 
   ~WindowTreeHostMus() override;
 
   // Sets the bounds in dips.
   void SetBoundsFromServer(const gfx::Rect& bounds);
 
   ui::EventDispatchDetails SendEventToProcessor(ui::Event* event) {
@@ skipping 32 matching lines @@
   bool in_set_bounds_from_server_ = false;
 
   std::unique_ptr<InputMethodMus> input_method_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowTreeHostMus);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_MUS_WINDOW_TREE_HOST_MUS_H_