Re-Reland: Implement features in NativeViewHostAura for scroll end effect

ui/views/controls/native/native_view_host_wrapper.h

 // Copyright (c) 2011 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_VIEWS_CONTROLS_NATIVE_NATIVE_VIEW_HOST_WRAPPER_H_
 #define UI_VIEWS_CONTROLS_NATIVE_NATIVE_VIEW_HOST_WRAPPER_H_
 
 #include "ui/gfx/native_widget_types.h"
 #include "ui/views/views_export.h"
 
 namespace views {
 
 class NativeViewHost;
 
 // An interface that implemented by an object that wraps a gfx::NativeView on
 // a specific platform, used to perform platform specific operations on that
 // native view when attached, detached, moved and sized.
 class VIEWS_EXPORT NativeViewHostWrapper {
  public:
   virtual ~NativeViewHostWrapper() {}
 
-  // Called right before a gfx::NativeView is attached to the associated
-  // NativeViewHost, allowing the wrapper to perform platform-specific
-  // initialization.
-  virtual void NativeViewWillAttach() = 0;
+  // Called at the end of NativeViewHost::Attach, allowing the wrapper to
+  // perform platform-specific operations that need to occur to complete
+  // attaching the gfx::NativeView.
+  virtual void AttachNativeView() = 0;
 
   // Called before the attached gfx::NativeView is detached from the
   // NativeViewHost, allowing the wrapper to perform platform-specific
   // cleanup. |destroyed| is true if the native view is detached
   // because it's being destroyed, or false otherwise.
   virtual void NativeViewDetaching(bool destroyed) = 0;
 
   // Called when our associated NativeViewHost is added to a View hierarchy
   // rooted at a valid Widget.
   virtual void AddedToWidget() = 0;
 
   // Called when our associated NativeViewHost is removed from a View hierarchy
   // rooted at a valid Widget.
   virtual void RemovedFromWidget() = 0;
 
-  // Installs a clip on the gfx::NativeView.
+  // Installs a clip on the gfx::NativeView. These values are in the coordinate
+  // space of the gfx::NativeView, so if this method is called from ShowWidget
+  // then the values need to be translated.
   virtual void InstallClip(int x, int y, int w, int h) = 0;
 
   // Whether or not a clip has been installed on the wrapped gfx::NativeView.
   virtual bool HasInstalledClip() = 0;
 
-  // Removes the clip installed on the gfx::NativeView by way of InstallClip.
+  // Removes the clip installed on the gfx::NativeView by way of InstallClip. A
+  // following call to ShowWidget should occur after calling this method to
+  // position the gfx::NativeView correctly, since the clipping process may have
+  // adjusted its position.
   virtual void UninstallClip() = 0;
 
   // Shows the gfx::NativeView at the specified position (relative to the parent
   // native view).
   virtual void ShowWidget(int x, int y, int w, int h) = 0;
 
   // Hides the gfx::NativeView. NOTE: this may be invoked when the native view
   // is already hidden.
   virtual void HideWidget() = 0;
 
   // Sets focus to the gfx::NativeView.
   virtual void SetFocus() = 0;
 
   // Return the native view accessible corresponding to the wrapped native
   // view.
   virtual gfx::NativeViewAccessible GetNativeViewAccessible() = 0;
 
   // Creates a platform-specific instance of an object implementing this
   // interface.
   static NativeViewHostWrapper* CreateWrapper(NativeViewHost* host);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_NATIVE_NATIVE_VIEW_HOST_WRAPPER_H_