Make WindowAndroid a ViewAndroid

ui/android/view_android.h

 // Copyright 2013 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_ANDROID_VIEW_ANDROID_H_
 #define UI_ANDROID_VIEW_ANDROID_H_
 
 #include <list>
 
 #include "base/android/scoped_java_ref.h"
 #include "base/memory/ref_counted.h"
 #include "ui/android/ui_android_export.h"
 
 namespace cc {
 class Layer;
 }
 
 namespace ui {
 
 class WindowAndroid;
 
 // A simple container for a UI layer.
-// At the root of the hierarchy is a WindowAndroid.
-//
+// At the root of the hierarchy is a WindowAndroid, when attached.
 class UI_ANDROID_EXPORT ViewAndroid {
  public:
-  // Used to construct a root view.
-  ViewAndroid(const base::android::JavaRef<jobject>& delegate,
-              WindowAndroid* root_window);
-
-  // Used to construct a child view.
+  // A ViewAndroid may have its own delegate or otherwise will
+  // use the next available parent's delegate.
+  ViewAndroid(const base::android::JavaRef<jobject>& delegate);
   ViewAndroid();
-  ~ViewAndroid();
+  virtual ~ViewAndroid();
 
   // Returns the window at the root of this hierarchy, or |null|
   // if disconnected.
-  WindowAndroid* GetWindowAndroid() const;
-
-  // Set the root |WindowAndroid|. This is only valid for root
-  // nodes and must not be called for children.
-  void SetWindowAndroid(WindowAndroid* root_window);
+  virtual WindowAndroid* GetWindowAndroid();
 
   // Returns the Java delegate for this view. This is used to delegate work
   // up to the embedding view (or the embedder that can deal with the
   // implementation details).
   const base::android::JavaRef<jobject>& GetViewAndroidDelegate() const;
 
   // Used to return and set the layer for this view. May be |null|.
   cc::Layer* GetLayer() const;
   void SetLayer(scoped_refptr<cc::Layer> layer);
 
-  // Add/remove this view as a child of another view.
+  // Adds this view as a child of another view.
   void AddChild(ViewAndroid* child);
+
+  // Detaches this view from its parent.
+  void RemoveFromParent();
+
+ protected:
+  ViewAndroid* parent_;
+
+ private:
   void RemoveChild(ViewAndroid* child);
 
- private:
-  ViewAndroid* parent_;
   std::list<ViewAndroid*> children_;
-  WindowAndroid* window_;
   scoped_refptr<cc::Layer> layer_;
   base::android::ScopedJavaGlobalRef<jobject> delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(ViewAndroid);
 };
 
 }  // namespace ui
 
 #endif  // UI_ANDROID_VIEW_ANDROID_H_