Cleanup: remove redundant tab close observation from TabModalConfirmDialogDelegate

chrome/browser/repost_form_warning_controller.cc

 // 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.
 
 #include "chrome/browser/repost_form_warning_controller.h"
 
 #if defined(TOOLKIT_GTK)
 #include <gtk/gtk.h>
 #endif
 
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/web_contents.h"
 #include "grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 
 RepostFormWarningController::RepostFormWarningController(
     content::WebContents* web_contents)
-    : TabModalConfirmDialogDelegate(web_contents),
-      content::WebContentsObserver(web_contents) {
+    : content::WebContentsObserver(web_contents) {
 }
 
 RepostFormWarningController::~RepostFormWarningController() {
 }
 
 string16 RepostFormWarningController::GetTitle() {
   return l10n_util::GetStringUTF16(IDS_HTTP_POST_WARNING_TITLE);
 }
 
 string16 RepostFormWarningController::GetMessage() {
@@ skipping 22 matching lines @@
 
 void RepostFormWarningController::OnCanceled() {
   web_contents()->GetController().CancelPendingReload();
 }
 
 void RepostFormWarningController::BeforeFormRepostWarningShow() {
   // Close the dialog if we show an additional dialog, to avoid them
   // stacking up.
   Cancel();
 }