Stops javascript alerts and unload dialogs from showing during

chrome/browser/tab_contents/tab_contents.cc

 // Copyright (c) 2010 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/tab_contents/tab_contents.h"
 
 #include <cmath>
 
 #include "app/l10n_util.h"
 #include "app/resource_bundle.h"
@@ skipping 2736 matching lines @@
     const GURL& frame_url,
     const int flags,
     IPC::Message* reply_msg,
     bool* did_suppress_message) {
   // Suppress javascript messages when requested and when inside a constrained
   // popup window (because that activates them and breaks them out of the
   // constrained window jail).
   // Also suppress messages when showing an interstitial. The interstitial is
   // shown over the previous page, we don't want the hidden page dialogs to
   // interfere with the interstitial.
-  bool suppress_this_message = suppress_javascript_messages_ ||
-                               showing_interstitial_page();
+  bool suppress_this_message =
+      suppress_javascript_messages_ ||
+      showing_interstitial_page() ||
+      (delegate() && delegate()->ShouldSuppressDialogs());
   if (delegate())
     suppress_this_message |=
         (delegate()->GetConstrainingContents(this) != this);
 
   *did_suppress_message = suppress_this_message;
 
   if (!suppress_this_message) {
     base::TimeDelta time_since_last_message(
         base::TimeTicks::Now() - last_javascript_message_dismissal_);
     bool show_suppress_checkbox = false;
     // Show a checkbox offering to suppress further messages if this message is
     // being displayed within kJavascriptMessageExpectedDelay of the last one.
     if (time_since_last_message <
         base::TimeDelta::FromMilliseconds(kJavascriptMessageExpectedDelay))
       show_suppress_checkbox = true;
 
     RunJavascriptMessageBox(profile(), this, frame_url, flags, message,
                             default_prompt, show_suppress_checkbox, reply_msg);
   } else {
     // If we are suppressing messages, just reply as is if the user immediately
     // pressed "Cancel".
     OnMessageBoxClosed(reply_msg, false, std::wstring());
   }
 }
 
 void TabContents::RunBeforeUnloadConfirm(const std::wstring& message,
                                          IPC::Message* reply_msg) {
+  if (delegate() && delegate()->ShouldSuppressDialogs()) {
+    render_view_host()->JavaScriptMessageBoxClosed(reply_msg, true,
+                                                   std::wstring());
+    return;
+  }
   is_showing_before_unload_dialog_ = true;
   RunBeforeUnloadDialog(this, message, reply_msg);
 }
 
 void TabContents::ShowModalHTMLDialog(const GURL& url, int width, int height,
                                       const std::string& json_arguments,
                                       IPC::Message* reply_msg) {
   if (delegate()) {
     HtmlDialogUIDelegate* dialog_delegate =
         new ModalHtmlDialogDelegate(url, width, height, json_arguments,
@@ skipping 440 matching lines @@
 }
 
 void TabContents::set_encoding(const std::string& encoding) {
   encoding_ = CharacterEncoding::GetCanonicalEncodingNameByAliasName(encoding);
 }
 
 void TabContents::SetAppIcon(const SkBitmap& app_icon) {
   app_icon_ = app_icon;
   NotifyNavigationStateChanged(INVALIDATE_TITLE);
 }