Remove TabContents from constrained windows.

chrome/browser/ui/cocoa/tab_modal_confirm_dialog_mac.mm

 // 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 "chrome/browser/ui/cocoa/tab_modal_confirm_dialog_mac.h"
 
 #include "base/command_line.h"
 #include "base/memory/scoped_nsobject.h"
 #include "chrome/browser/ui/browser_dialogs.h"
 #include "chrome/browser/ui/cocoa/constrained_window/constrained_window_alert.h"
@@ skipping 64 matching lines @@
   [alert addButtonWithTitle:
       l10n_util::FixUpWindowsStyleLabel(delegate->GetAcceptButtonTitle())];
   [alert addButtonWithTitle:
       l10n_util::FixUpWindowsStyleLabel(delegate->GetCancelButtonTitle())];
   gfx::Image* icon = delegate->GetIcon();
   if (icon)
     [alert setIcon:icon->ToNSImage()];
 
   set_sheet(alert);
 
-  delegate->set_window(new ConstrainedWindowMac(tab_contents, this));
+  delegate->set_window(
+      new ConstrainedWindowMac(tab_contents->web_contents(), this));
 }
 
 TabModalConfirmDialogMac::~TabModalConfirmDialogMac() {
   CancelTabModalDialog();
 }
 
 // "DeleteDelegate" refers to this class being a ConstrainedWindow delegate
 // and deleting itself, not to deleting the member variable |delegate_|.
 void TabModalConfirmDialogMac::DeleteDelegate() {
   delete this;
@@ skipping 61 matching lines @@
   [alert_ addButtonWithTitle:
       l10n_util::FixUpWindowsStyleLabel(delegate->GetCancelButtonTitle())
               keyEquivalent:kKeyEquivalentEscape
                      target:bridge_
                      action:@selector(onCancelButton:)];
   [[alert_ closeButton] setTarget:bridge_];
   [[alert_ closeButton] setAction:@selector(onCancelButton:)];
   [alert_ layout];
 
   delegate->set_window(
-      new ConstrainedWindowMac2(tab_contents, [alert_ window]));
+      new ConstrainedWindowMac2(tab_contents->web_contents(), [alert_ window]));
 }
 
 TabModalConfirmDialogMac2::~TabModalConfirmDialogMac2() {
 }
 
 void TabModalConfirmDialogMac2::AcceptTabModalDialog() {
 }
 
 void TabModalConfirmDialogMac2::CancelTabModalDialog() {
 }