Implement NativeViewHostAura::InstallClip.

content/browser/web_contents/web_contents_view_aura.cc

 // 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.
 
 #include "content/browser/web_contents/web_contents_view_aura.h"
 
 #include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/file_util.h"
 #include "base/metrics/histogram.h"
@@ skipping 540 matching lines @@
         window->parent() == view_->window_->GetRootWindow()) {
       UpdateConstrainedWindows(NULL);
     }
   }
 #endif
 
   virtual void OnWindowParentChanged(aura::Window* window,
                                      aura::Window* parent) OVERRIDE {
     if (window != view_->window_)
       return;
+
+    // Since all native views are hosted inside a clipping window, the actual
+    // parent that we care about is the clipping window's parent.
+    if (parent)

[sky, 2014/06/16 17:11:03]

That a different parent exists is an implementation detail of NativeViewHost. If
that changes this code will break and we may now know. We need a better way to
be insulated from changes in NativeViewHost. Maybe a method on NativeViewHost?

[calamity, 2014/06/17 05:01:12]

Since this operates at the window level, I don't think there's a way to ask the
relevant NativeViewHost about this. Maybe a static method that checks if the
window name matches the clipping window's name?

Another option is to static_cast the NativeViewHost out of the window's
kHostViewKey and use host->GetWidget()->GetNativeView().

[sky, 2014/06/17 16:25:25]

Neither of these options work since this code shouldn't know about views. Also,
since this code isn't necessarily used with views assuming views is being used
is equally wrong. Also, isn't the code in UpdateConstrainedWindow going to
incorrectly consider the clipping window?

I think we're going to need some way to tag (similar to kHostViewKey) which
parent is used but is exposed in a place this code can access.

+      parent = parent->parent();
+
     if (parent_)
       parent_->RemoveObserver(this);
 
 #if defined(OS_WIN)
     if (parent_) {
       const aura::Window::Windows& children = parent_->children();
       for (size_t i = 0; i < children.size(); ++i)
         children[i]->RemoveObserver(this);
 
       RenderWidgetHostViewAura* view = ToRenderWidgetHostViewAura(
@@ skipping 95 matching lines @@
   void UpdateConstrainedWindows(aura::Window* exclude) {
     RenderWidgetHostViewAura* view = ToRenderWidgetHostViewAura(
         view_->web_contents_->GetRenderWidgetHostView());
     if (!view)
       return;
 
     std::vector<gfx::Rect> constrained_windows;
     if (parent_) {
       const aura::Window::Windows& children = parent_->children();
       for (size_t i = 0; i < children.size(); ++i) {
-        if (children[i] != view_->window_ &&
+        if (children[i] != view_->window_->parent() &&
             children[i] != exclude &&
             children[i]->IsVisible()) {
           constrained_windows.push_back(children[i]->GetBoundsInRootWindow());
         }
       }
     }
 
     aura::Window* root_window = view_->window_->GetRootWindow();
     const aura::Window::Windows& root_children = root_window->children();
     if (root_window) {
@@ skipping 884 matching lines @@
 void WebContentsViewAura::OnWindowVisibilityChanged(aura::Window* window,
                                                     bool visible) {
   // Ignore any visibility changes in the hierarchy below.
   if (window != window_.get() && window_->Contains(window))
     return;
 
   UpdateWebContentsVisibility(web_contents_, visible);
 }
 
 }  // namespace content