Keep a web dialog window centered over the content area

ui/aura/window.h

 // Copyright (c) 2012 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_WINDOW_H_
 #define UI_AURA_WINDOW_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 341 matching lines @@
 
   // Overridden from ui::LayerDelegate:
   virtual void OnDeviceScaleFactorChanged(float device_scale_factor) OVERRIDE;
 
 #ifndef NDEBUG
   // These methods are useful when debugging.
   std::string GetDebugInfo() const;
   void PrintWindowHierarchy(int depth) const;
 #endif
 
+  // Returns true if the window is a constrained window.
+  void set_is_constrained_window(bool is_constrained_window) {

[sky, 2012/09/14 22:50:44]

Window shouldn't contain chrome specific properties like this. By property I
meant something via SetProperty.

+    is_constrained_window_ = is_constrained_window;
+  }
+  bool is_constrained_window() const { return is_constrained_window_; }
+
  private:
   friend class LayoutManager;
 
   // Used when stacking windows.
   enum StackDirection {
     STACK_ABOVE,
     STACK_BELOW
   };
 
   // Called by the public {Set,Get,Clear}Property functions.
@@ skipping 121 matching lines @@
   // Key cannot be used for this purpose because it can be char* or
   // WindowProperty<>.
   struct Value {
     const char* name;
     intptr_t value;
     PropertyDeallocator deallocator;
   };
 
   std::map<const void*, Value> prop_map_;
 
+  // True if this is a constrained window.
+  bool is_constrained_window_;
+
   DISALLOW_COPY_AND_ASSIGN(Window);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_WINDOW_H_