Implement window.alert() and its cousins for extensions.

BUG=12126
TEST=put a window.prompt() in a background page, a browser action, and a page action.
  Make sure it gets the result back correctly.  Also make sure it still works when
  called from a web page.
Review URL: http://codereview.chromium.org/341089

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@31110 0039d316-1c4b-4281-b951-d872f2087c98

14 files changed, 242 insertions, 107 deletions

diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index d2f5b066..32ff803 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -2765,19 +2765,31 @@ Keep your key file in a safe place. You will need it to create new versions of y
       </message>
 
       <!-- Javascript Dialog Box strings -->
-      <message name="IDS_JAVASCRIPT_ALERT_DEFAULT_TITLE" desc="Title for Javascript alert if there is no hostname to display">
+      <message name="IDS_JAVASCRIPT_ALERT_DEFAULT_TITLE" desc="Title for Javascript alert originating from a web page if there is no hostname to display">
         Javascript Alert
       </message>
-      <message name="IDS_JAVASCRIPT_MESSAGEBOX_DEFAULT_TITLE" desc="Title for Javascript prompt and confirm if there is no hostname to display">
+      <message name="IDS_JAVASCRIPT_MESSAGEBOX_DEFAULT_TITLE" desc="Title for Javascript prompt and confirm originating from a web page if there is no hostname to display">
         Javascript
       </message>
-      <message name="IDS_JAVASCRIPT_ALERT_TITLE" desc="Title for Javascript alert">
+      <message name="IDS_JAVASCRIPT_ALERT_TITLE" desc="Title for Javascript alert originating from a web page">
         Alert <ph name="SITE">$1<ex>http://www.google.com</ex>
         </ph>
       </message>
-      <message name="IDS_JAVASCRIPT_MESSAGEBOX_TITLE" desc="Title for Javascript prompt and confirm">
+      <message name="IDS_JAVASCRIPT_MESSAGEBOX_TITLE" desc="Title for Javascript prompt and confirm originating from a web page">
         <ph name="SITE">$1<ex>http://www.google.com</ex></ph>
       </message>
+      <message name="IDS_EXTENSION_ALERT_DEFAULT_TITLE" desc="Title for Javascript alert originating from an extension if there is no extension name to display">
+        Extension Alert
+      </message>
+      <message name="IDS_EXTENSION_MESSAGEBOX_DEFAULT_TITLE" desc="Title for Javascript prompt and confirm originating from an extension if there is no extension name to display">
+        Extension
+      </message>
+      <message name="IDS_EXTENSION_ALERT_TITLE" desc="Title for Javascript alert originating from an extension">
+        Extension Alert <ph name="EXTENSION_NAME">$1<ex>Gmail Checker</ex></ph>
+      </message>
+      <message name="IDS_EXTENSION_MESSAGEBOX_TITLE" desc="Title for Javascript prompt and confirm originating from an extension">
+        Extension <ph name="EXTENSION_NAME">$1<ex>Gmail Checker</ex></ph>
+      </message>
       <message name="IDS_JAVASCRIPT_MESSAGEBOX_SUPPRESS_OPTION" desc="Optional UI shown on the message box, in the form of a checkbox, allowing the user to suppress additional message boxes from the page.">
         Prevent this page from creating additional dialogs.
       </message>
diff --git a/chrome/browser/app_modal_dialog.cc b/chrome/browser/app_modal_dialog.cc
index 8abf78e..4da37d7 100644
--- a/chrome/browser/app_modal_dialog.cc
+++ b/chrome/browser/app_modal_dialog.cc
@@ -10,7 +10,7 @@
 #include "chrome/common/notification_type.h"
 #include "ipc/ipc_message.h"
 
-AppModalDialog::AppModalDialog(TabContents* tab_contents,
+AppModalDialog::AppModalDialog(JavaScriptMessageBoxClient* client,
                                const std::wstring& title,
                                int dialog_flags,
                                const std::wstring& message_text,
@@ -19,7 +19,8 @@ AppModalDialog::AppModalDialog(TabContents* tab_contents,
                                bool is_before_unload_dialog,
                                IPC::Message* reply_msg)
     : dialog_(NULL),
-      tab_contents_(tab_contents),
+      client_(client),
+      skip_this_dialog_(false),
       title_(title),
       dialog_flags_(dialog_flags),
       message_text_(message_text),
@@ -33,20 +34,20 @@ AppModalDialog::AppModalDialog(TabContents* tab_contents,
 void AppModalDialog::Observe(NotificationType type,
                              const NotificationSource& source,
                              const NotificationDetails& details) {
-  if (!tab_contents_)
+  const TabContents* tab_contents = client_->AsTabContents();
+  if (!tab_contents)
     return;
 
   if (type == NotificationType::NAV_ENTRY_COMMITTED &&
       Source<NavigationController>(source).ptr() ==
-          &tab_contents_->controller())
-    tab_contents_ = NULL;
+          &tab_contents->controller())
+    skip_this_dialog_ = true;
 
   if (type == NotificationType::TAB_CONTENTS_DESTROYED &&
-      Source<TabContents>(source).ptr() ==
-      static_cast<TabContents*>(tab_contents_))
-    tab_contents_ = NULL;
+      Source<TabContents>(source).ptr() == tab_contents)
+    skip_this_dialog_ = true;
 
-  if (!tab_contents_)
+  if (skip_this_dialog_)
     CloseModalDialog();
 }
 
@@ -60,22 +61,26 @@ void AppModalDialog::SendCloseNotification() {
 void AppModalDialog::InitNotifications() {
   // Make sure we get navigation notifications so we know when our parent
   // contents will disappear or navigate to a different page.
-  registrar_.Add(this, NotificationType::NAV_ENTRY_COMMITTED,
-                 NotificationService::AllSources());
-  registrar_.Add(this, NotificationType::TAB_CONTENTS_DESTROYED,
-                 NotificationService::AllSources());
+  if (client_->AsTabContents()) {
+    registrar_.Add(this, NotificationType::NAV_ENTRY_COMMITTED,
+                   NotificationService::AllSources());
+    registrar_.Add(this, NotificationType::TAB_CONTENTS_DESTROYED,
+                   NotificationService::AllSources());
+  }
 }
 
 void AppModalDialog::ShowModalDialog() {
   // If the TabContents that created this dialog navigated away before this
   // dialog became visible, simply show the next dialog if any.
-  if (!tab_contents_) {
+  if (skip_this_dialog_) {
     Singleton<AppModalDialogQueue>()->ShowNextDialog();
     delete this;
     return;
   }
+  TabContents* tab_contents = client_->AsTabContents();
+  if (tab_contents)
+    tab_contents->Activate();
 
-  tab_contents_->Activate();
   CreateAndShowDialog();
 
   NotificationService::current()->Notify(
@@ -86,16 +91,15 @@ void AppModalDialog::ShowModalDialog() {
 
 void AppModalDialog::OnCancel() {
   // We need to do this before WM_DESTROY (WindowClosing()) as any parent frame
-  // will receive it's activation messages before this dialog receives
+  // will receive its activation messages before this dialog receives
   // WM_DESTROY. The parent frame would then try to activate any modal dialogs
   // that were still open in the ModalDialogQueue, which would send activation
   // back to this one. The framework should be improved to handle this, so this
   // is a temporary workaround.
   Singleton<AppModalDialogQueue>()->ShowNextDialog();
 
-  if (tab_contents_) {
-    tab_contents_->OnJavaScriptMessageBoxClosed(reply_msg_, false,
-                                                std::wstring());
+  if (!skip_this_dialog_) {
+    client_->OnMessageBoxClosed(reply_msg_, false, std::wstring());
   }
 
   SendCloseNotification();
@@ -105,12 +109,10 @@ void AppModalDialog::OnAccept(const std::wstring& prompt_text,
                               bool suppress_js_messages) {
   Singleton<AppModalDialogQueue>()->ShowNextDialog();
 
-  if (tab_contents_) {
-    tab_contents_->OnJavaScriptMessageBoxClosed(reply_msg_, true,
-                                                prompt_text);
-
+  if (!skip_this_dialog_) {
+    client_->OnMessageBoxClosed(reply_msg_, true, prompt_text);
     if (suppress_js_messages)
-      tab_contents()->set_suppress_javascript_messages(true);
+      client_->SetSuppressMessageBoxes(true);
   }
 
   SendCloseNotification();
diff --git a/chrome/browser/app_modal_dialog.h b/chrome/browser/app_modal_dialog.h
index 8d44d64..8263565 100644
--- a/chrome/browser/app_modal_dialog.h
+++ b/chrome/browser/app_modal_dialog.h
@@ -21,7 +21,7 @@ typedef GtkWidget* NativeDialog;
 typedef void* NativeDialog;
 #endif
 
-class TabContents;
+class JavaScriptMessageBoxClient;
 namespace IPC {
 class Message;
 }
@@ -33,7 +33,7 @@ class AppModalDialog : public NotificationObserver {
  public:
   // A union of data necessary to determine the type of message box to
   // show.  |dialog_flags| is a MessageBox flag.
-  AppModalDialog(TabContents* tab_contents,
+  AppModalDialog(JavaScriptMessageBoxClient* client,
                  const std::wstring& title,
                  int dialog_flags,
                  const std::wstring& message_text,
@@ -63,8 +63,8 @@ class AppModalDialog : public NotificationObserver {
 
   /////////////////////////////////////////////////////////////////////////////
   // Getters so NativeDialog can get information about the message box.
-  TabContents* tab_contents() {
-    return tab_contents_;
+  JavaScriptMessageBoxClient* client() {
+    return client_;
   }
   int dialog_flags() {
     return dialog_flags_;
@@ -103,8 +103,15 @@ class AppModalDialog : public NotificationObserver {
   // A reference to the platform native dialog box.
   NativeDialog dialog_;
 
+  // An implementation of the client interface to provide supporting methods
+  // and receive results.
+  JavaScriptMessageBoxClient* client_;
+
+  // True if the dialog should no longer be shown, e.g. because the underlying
+  // tab navigated away while the dialog was queued.
+  bool skip_this_dialog_;
+
   // Information about the message box is held in the following variables.
-  TabContents* tab_contents_;
   std::wstring title_;
   int dialog_flags_;
   std::wstring message_text_;
diff --git a/chrome/browser/app_modal_dialog_gtk.cc b/chrome/browser/app_modal_dialog_gtk.cc
index 0191e84..d3bbd48 100644
--- a/chrome/browser/app_modal_dialog_gtk.cc
+++ b/chrome/browser/app_modal_dialog_gtk.cc
@@ -122,7 +122,7 @@ void AppModalDialog::CreateAndShowDialog() {
   }
   g_object_unref(window_group);
 
-  GtkWindow* window = tab_contents_->view()->GetTopLevelNativeWindow();
+  gfx::NativeWindow window = client_->GetMessageBoxRootWindow();
   dialog_ = gtk_message_dialog_new(window, GTK_DIALOG_MODAL,
       message_type, buttons, "%s", WideToUTF8(message_text_).c_str());
   gtk_window_set_title(GTK_WINDOW(dialog_), WideToUTF8(title_).c_str());
diff --git a/chrome/browser/extensions/extension_host.cc b/chrome/browser/extensions/extension_host.cc
index f9d6bd1..e2cea15 100644
--- a/chrome/browser/extensions/extension_host.cc
+++ b/chrome/browser/extensions/extension_host.cc
@@ -6,6 +6,7 @@
 
 #include <list>
 
+#include "app/l10n_util.h"
 #include "app/resource_bundle.h"
 #include "base/message_loop.h"
 #include "base/singleton.h"
@@ -18,6 +19,7 @@
 #include "chrome/browser/dom_ui/dom_ui_factory.h"
 #include "chrome/browser/extensions/extension_message_service.h"
 #include "chrome/browser/extensions/extension_tabs_module.h"
+#include "chrome/browser/jsmessage_box_handler.h"
 #include "chrome/browser/extensions/extension_popup_api.h"
 #include "chrome/browser/profile.h"
 #include "chrome/browser/renderer_host/render_view_host.h"
@@ -25,6 +27,8 @@
 #include "chrome/browser/renderer_host/render_widget_host.h"
 #include "chrome/browser/renderer_host/render_widget_host_view.h"
 #include "chrome/browser/renderer_host/site_instance.h"
+#include "chrome/browser/tab_contents/tab_contents.h"
+#include "chrome/browser/tab_contents/tab_contents_view.h"
 #include "chrome/common/bindings_policy.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/notification_service.h"
@@ -34,6 +38,7 @@
 #include "chrome/common/render_messages.h"
 #include "chrome/common/url_constants.h"
 #include "grit/browser_resources.h"
+#include "grit/generated_resources.h"
 #include "webkit/glue/context_menu.h"
 
 #if defined(TOOLKIT_VIEWS)
@@ -397,10 +402,37 @@ void ExtensionHost::RunJavaScriptMessage(const std::wstring& message,
                                          const int flags,
                                          IPC::Message* reply_msg,
                                          bool* did_suppress_message) {
-  // Automatically cancel the javascript alert (otherwise the renderer hangs
-  // indefinitely).
-  *did_suppress_message = true;
-  render_view_host()->JavaScriptMessageBoxClosed(reply_msg, true, L"");
+  *did_suppress_message = false;
+  // Unlike for page alerts, navigations aren't a good signal for when to
+  // resume showing alerts, so we can't reasonably stop showing them even if
+  // the extension is spammy.
+  RunJavascriptMessageBox(this, frame_url, flags, message, default_prompt,
+                          false, reply_msg);
+}
+
+std::wstring ExtensionHost::GetMessageBoxTitle(const GURL& frame_url,
+                                               bool is_alert) {
+  if (extension_->name().empty())
+    return l10n_util::GetString(
+        is_alert ? IDS_EXTENSION_ALERT_DEFAULT_TITLE
+                 : IDS_EXTENSION_MESSAGEBOX_DEFAULT_TITLE);
+
+  return l10n_util::GetStringF(
+      is_alert ? IDS_EXTENSION_ALERT_TITLE : IDS_EXTENSION_MESSAGEBOX_TITLE,
+      UTF8ToWide(extension_->name()));
+}
+
+gfx::NativeWindow ExtensionHost::GetMessageBoxRootWindow() {
+  TabContents* active_tab = GetBrowser()->GetSelectedTabContents();
+  if (active_tab)
+    return active_tab->view()->GetTopLevelNativeWindow();
+  return NULL;
+}
+
+void ExtensionHost::OnMessageBoxClosed(IPC::Message* reply_msg,
+                                       bool success,
+                                       const std::wstring& prompt) {
+  render_view_host()->JavaScriptMessageBoxClosed(reply_msg, success, prompt);
 }
 
 void ExtensionHost::Close(RenderViewHost* render_view_host) {
diff --git a/chrome/browser/extensions/extension_host.h b/chrome/browser/extensions/extension_host.h
index bf66579..22279a1 100644
--- a/chrome/browser/extensions/extension_host.h
+++ b/chrome/browser/extensions/extension_host.h
@@ -9,6 +9,7 @@
 
 #include "base/scoped_ptr.h"
 #include "chrome/browser/extensions/extension_function_dispatcher.h"
+#include "chrome/browser/jsmessage_box_client.h"
 #include "chrome/browser/renderer_host/render_view_host_delegate.h"
 #include "chrome/browser/tab_contents/render_view_host_delegate_helper.h"
 #if defined(TOOLKIT_VIEWS)
@@ -45,7 +46,8 @@ class ExtensionHost :  // NOLINT
                       public RenderViewHostDelegate,
                       public RenderViewHostDelegate::View,
                       public ExtensionFunctionDispatcher::Delegate,
-                      public NotificationObserver {
+                      public NotificationObserver,
+                      public JavaScriptMessageBoxClient {
  public:
   class ProcessCreationQueue;
 
@@ -174,6 +176,16 @@ class ExtensionHost :  // NOLINT
                        const NotificationSource& source,
                        const NotificationDetails& details);
 
+  // JavaScriptMessageBoxClient
+  virtual std::wstring GetMessageBoxTitle(const GURL& frame_url,
+                                          bool is_alert);
+  virtual gfx::NativeWindow GetMessageBoxRootWindow();
+  virtual void OnMessageBoxClosed(IPC::Message* reply_msg,
+                                  bool success,
+                                  const std::wstring& prompt);
+  virtual void SetSuppressMessageBoxes(bool suppress_message_boxes) {}
+  virtual TabContents* AsTabContents() { return NULL; }
+
  private:
   friend class ProcessCreationQueue;
 
diff --git a/chrome/browser/jsmessage_box_client.h b/chrome/browser/jsmessage_box_client.h
new file mode 100644
index 0000000..5e60c5d
--- /dev/null
+++ b/chrome/browser/jsmessage_box_client.h
@@ -0,0 +1,50 @@
+// Copyright (c) 2009 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 CHROME_BROWSER_JSMESSAGE_BOX_CLIENT_H_
+#define CHROME_BROWSER_JSMESSAGE_BOX_CLIENT_H_
+
+// JavaScriptMessageBoxClient
+//
+// An interface implemented by an object that receives results from JavaScript
+// message boxes (alert, confirm, and prompt).
+//
+
+#include <string>
+
+#include "app/gfx/native_widget_types.h"
+
+class GURL;
+class Profile;
+class TabContents;
+namespace IPC {
+class Message;
+}
+
+class JavaScriptMessageBoxClient {
+ public:
+  virtual ~JavaScriptMessageBoxClient() {}
+
+  // Returns the title to use for the message box.
+  virtual std::wstring GetMessageBoxTitle(const GURL& frame_url,
+                                          bool is_alert) = 0;
+
+  // Returns the root native window with which the message box is associated.
+  virtual gfx::NativeWindow GetMessageBoxRootWindow() = 0;
+
+  // AppModalDialog calls this when the dialog is closed.
+  virtual void OnMessageBoxClosed(IPC::Message* reply_msg,
+                                  bool success,
+                                  const std::wstring& prompt) = 0;
+
+  // Indicates whether additional message boxes should be suppressed.
+  virtual void SetSuppressMessageBoxes(bool suppress_message_boxes) = 0;
+
+  // Returns the TabContents associated with this message box -- in practice,
+  // the TabContents implementing this interface -- or NULL if it has no
+  // TabContents (e.g., it's an ExtensionHost).
+  virtual TabContents* AsTabContents() = 0;
+};
+
+# endif  // CHROME_BROWSER_JSMESSAGE_BOX_CLIENT_H_
diff --git a/chrome/browser/jsmessage_box_handler.cc b/chrome/browser/jsmessage_box_handler.cc
index 6ba052f..428c8a3 100644
--- a/chrome/browser/jsmessage_box_handler.cc
+++ b/chrome/browser/jsmessage_box_handler.cc
@@ -4,16 +4,12 @@
 
 #include "chrome/browser/jsmessage_box_handler.h"
 
-#include "app/gfx/text_elider.h"
 #include "app/l10n_util.h"
 #include "app/message_box_flags.h"
 #include "build/build_config.h"
 #include "chrome/browser/app_modal_dialog_queue.h"
 #include "chrome/browser/browser_process.h"
-#include "chrome/browser/profile.h"
 #include "chrome/browser/tab_contents/tab_contents.h"
-#include "chrome/common/pref_names.h"
-#include "chrome/common/pref_service.h"
 #include "googleurl/src/gurl.h"
 #include "grit/generated_resources.h"
 
@@ -29,47 +25,19 @@ std::wstring MakeTextSafe(const std::wstring& text) {
   return text;
 }
 
-std::wstring GetWindowTitle(TabContents* tab_contents, const GURL& frame_url,
-                            int dialog_flags) {
-  bool is_alert = (dialog_flags == MessageBoxFlags::kIsJavascriptAlert);
-  if (!frame_url.has_host())
-    return l10n_util::GetString(
-        is_alert ? IDS_JAVASCRIPT_ALERT_DEFAULT_TITLE
-                 : IDS_JAVASCRIPT_MESSAGEBOX_DEFAULT_TITLE);
-
-  // We really only want the scheme, hostname, and port.
-  GURL::Replacements replacements;
-  replacements.ClearUsername();
-  replacements.ClearPassword();
-  replacements.ClearPath();
-  replacements.ClearQuery();
-  replacements.ClearRef();
-  GURL clean_url = frame_url.ReplaceComponents(replacements);
-
-  // TODO(brettw) it should be easier than this to do the correct language
-  // handling without getting the accept language from the profile.
-  std::wstring base_address = gfx::ElideUrl(clean_url, gfx::Font(), 0,
-      tab_contents->profile()->GetPrefs()->GetString(prefs::kAcceptLanguages));
-  // Force URL to have LTR directionality.
-  if (l10n_util::GetTextDirection() == l10n_util::RIGHT_TO_LEFT)
-    l10n_util::WrapStringWithLTRFormatting(&base_address);
-  return l10n_util::GetStringF(
-      is_alert ? IDS_JAVASCRIPT_ALERT_TITLE : IDS_JAVASCRIPT_MESSAGEBOX_TITLE,
-      base_address);
-}
-
 }  // namespace
 
-void RunJavascriptMessageBox(TabContents* tab_contents,
+void RunJavascriptMessageBox(JavaScriptMessageBoxClient* client,
                              const GURL& frame_url,
                              int dialog_flags,
                              const std::wstring& message_text,
                              const std::wstring& default_prompt_text,
                              bool display_suppress_checkbox,
                              IPC::Message* reply_msg) {
-  std::wstring title = GetWindowTitle(tab_contents, frame_url, dialog_flags);
+  std::wstring title = client->GetMessageBoxTitle(frame_url,
+      (dialog_flags == MessageBoxFlags::kIsJavascriptAlert));
   Singleton<AppModalDialogQueue>()->AddDialog(
-      new AppModalDialog(tab_contents, title,
+      new AppModalDialog(client, title,
                          dialog_flags, MakeTextSafe(message_text),
                          default_prompt_text, display_suppress_checkbox,
                          false, reply_msg));
diff --git a/chrome/browser/jsmessage_box_handler.h b/chrome/browser/jsmessage_box_handler.h
index 856c1c5..9ec6652 100644
--- a/chrome/browser/jsmessage_box_handler.h
+++ b/chrome/browser/jsmessage_box_handler.h
@@ -10,6 +10,7 @@
 #include "ipc/ipc_message.h"
 
 class GURL;
+class JavaScriptMessageBoxClient;
 class TabContents;
 
 // Creates and runs a Javascript Message Box dialog.
@@ -18,7 +19,7 @@ class TabContents;
 // a user input prompt() box, the default text for the text field is in
 // |default_prompt_text|. The result of the operation is returned using
 // |reply_msg|.
-void RunJavascriptMessageBox(TabContents* tab_contents,
+void RunJavascriptMessageBox(JavaScriptMessageBoxClient* client,
                              const GURL& frame_url,
                              int dialog_flags,
                              const std::wstring& message_text,
diff --git a/chrome/browser/tab_contents/tab_contents.cc b/chrome/browser/tab_contents/tab_contents.cc
index e72df68..831b13c 100644
--- a/chrome/browser/tab_contents/tab_contents.cc
+++ b/chrome/browser/tab_contents/tab_contents.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/tab_contents/tab_contents.h"
 
+#include "app/gfx/text_elider.h"
 #include "app/l10n_util.h"
 #include "app/resource_bundle.h"
 #include "base/file_version_info.h"
@@ -1114,21 +1115,6 @@ void TabContents::GetPageLanguage() {
   render_view_host()->GetPageLanguage();
 }
 
-void TabContents::OnJavaScriptMessageBoxClosed(IPC::Message* reply_msg,
-                                               bool success,
-                                               const std::wstring& prompt) {
-  last_javascript_message_dismissal_ = base::TimeTicks::Now();
-  if (is_showing_before_unload_dialog_ && !success) {
-    // If a beforeunload dialog is canceled, we need to stop the throbber from
-    // spinning, since we forced it to start spinning in Navigate.
-    DidStopLoading();
-
-    tab_close_start_time_ = base::TimeTicks();
-  }
-  is_showing_before_unload_dialog_ = false;
-  render_view_host()->JavaScriptMessageBoxClosed(reply_msg, success, prompt);
-}
-
 void TabContents::OnSavePage() {
   // If we can not save the page, try to download it.
   if (!SavePackage::IsSavableContents(contents_mime_type())) {
@@ -2333,7 +2319,7 @@ void TabContents::RunJavaScriptMessage(
   } else {
     // If we are suppressing messages, just reply as is if the user immediately
     // pressed "Cancel".
-    OnJavaScriptMessageBoxClosed(reply_msg, false, std::wstring());
+    OnMessageBoxClosed(reply_msg, false, std::wstring());
   }
 }
 
@@ -2648,6 +2634,58 @@ void TabContents::Observe(NotificationType type,
   }
 }
 
+std::wstring TabContents::GetMessageBoxTitle(const GURL& frame_url,
+                                             bool is_alert) {
+  if (!frame_url.has_host())
+    return l10n_util::GetString(
+        is_alert ? IDS_JAVASCRIPT_ALERT_DEFAULT_TITLE
+                 : IDS_JAVASCRIPT_MESSAGEBOX_DEFAULT_TITLE);
+
+  // We really only want the scheme, hostname, and port.
+  GURL::Replacements replacements;
+  replacements.ClearUsername();
+  replacements.ClearPassword();
+  replacements.ClearPath();
+  replacements.ClearQuery();
+  replacements.ClearRef();
+  GURL clean_url = frame_url.ReplaceComponents(replacements);
+
+  // TODO(brettw) it should be easier than this to do the correct language
+  // handling without getting the accept language from the profile.
+  std::wstring base_address = gfx::ElideUrl(clean_url, gfx::Font(), 0,
+      profile()->GetPrefs()->GetString(prefs::kAcceptLanguages));
+  // Force URL to have LTR directionality.
+  if (l10n_util::GetTextDirection() == l10n_util::RIGHT_TO_LEFT)
+    l10n_util::WrapStringWithLTRFormatting(&base_address);
+
+  return l10n_util::GetStringF(
+      is_alert ? IDS_JAVASCRIPT_ALERT_TITLE : IDS_JAVASCRIPT_MESSAGEBOX_TITLE,
+      base_address);
+}
+
+gfx::NativeWindow TabContents::GetMessageBoxRootWindow() {
+  return view_->GetTopLevelNativeWindow();
+}
+
+void TabContents::OnMessageBoxClosed(IPC::Message* reply_msg,
+                                     bool success,
+                                     const std::wstring& prompt) {
+  last_javascript_message_dismissal_ = base::TimeTicks::Now();
+  if (is_showing_before_unload_dialog_ && !success) {
+    // If a beforeunload dialog is canceled, we need to stop the throbber from
+    // spinning, since we forced it to start spinning in Navigate.
+    DidStopLoading();
+
+    tab_close_start_time_ = base::TimeTicks();
+  }
+  is_showing_before_unload_dialog_ = false;
+  render_view_host()->JavaScriptMessageBoxClosed(reply_msg, success, prompt);
+}
+
+void TabContents::SetSuppressMessageBoxes(bool suppress_message_boxes) {
+  set_suppress_javascript_messages(suppress_message_boxes);
+}
+
 void TabContents::set_encoding(const std::string& encoding) {
   encoding_ = CharacterEncoding::GetCanonicalEncodingNameByAliasName(encoding);
 }
diff --git a/chrome/browser/tab_contents/tab_contents.h b/chrome/browser/tab_contents/tab_contents.h
index c33fcc5..7cdb549 100644
--- a/chrome/browser/tab_contents/tab_contents.h
+++ b/chrome/browser/tab_contents/tab_contents.h
@@ -22,6 +22,7 @@
 #include "chrome/browser/download/save_package.h"
 #include "chrome/browser/fav_icon_helper.h"
 #include "chrome/browser/find_notification_details.h"
+#include "chrome/browser/jsmessage_box_client.h"
 #include "chrome/browser/shell_dialogs.h"
 #include "chrome/browser/renderer_host/render_view_host_delegate.h"
 #include "chrome/browser/tab_contents/constrained_window.h"
@@ -97,7 +98,8 @@ class TabContents : public PageNavigator,
                     public RenderViewHostDelegate::BrowserIntegration,
                     public RenderViewHostDelegate::Resource,
                     public RenderViewHostManager::Delegate,
-                    public SelectFileDialog::Listener {
+                    public SelectFileDialog::Listener,
+                    public JavaScriptMessageBoxClient {
  public:
   // Flags passed to the TabContentsDelegate.NavigationStateChanged to tell it
   // what has changed. Combine them to update more than one thing.
@@ -533,11 +535,6 @@ class TabContents : public PageNavigator,
     suppress_javascript_messages_ = suppress_javascript_messages;
   }
 
-  // AppModalDialog calls this when the dialog is closed.
-  void OnJavaScriptMessageBoxClosed(IPC::Message* reply_msg,
-                                    bool success,
-                                    const std::wstring& prompt);
-
   // Prepare for saving the current web page to disk.
   void OnSavePage();
 
@@ -958,6 +955,17 @@ class TabContents : public PageNavigator,
                        const NotificationSource& source,
                        const NotificationDetails& details);
 
+
+  // JavaScriptMessageBoxClient ------------------------------------------------
+  virtual std::wstring GetMessageBoxTitle(const GURL& frame_url,
+                                          bool is_alert);
+  virtual gfx::NativeWindow GetMessageBoxRootWindow();
+  virtual void OnMessageBoxClosed(IPC::Message* reply_msg,
+                                  bool success,
+                                  const std::wstring& prompt);
+  virtual void SetSuppressMessageBoxes(bool suppress_message_boxes);
+  virtual TabContents* AsTabContents() { return this; }
+
   // Data for core operation ---------------------------------------------------
 
   // Delegate for notifying our owner about stuff. Not owned by us.
diff --git a/chrome/browser/views/jsmessage_box_dialog.cc b/chrome/browser/views/jsmessage_box_dialog.cc
index 3fb70e0..b83242f 100644
--- a/chrome/browser/views/jsmessage_box_dialog.cc
+++ b/chrome/browser/views/jsmessage_box_dialog.cc
@@ -37,10 +37,15 @@ JavascriptMessageBoxDialog::~JavascriptMessageBoxDialog() {
 }
 
 void JavascriptMessageBoxDialog::ShowModalDialog() {
-  HWND root_hwnd = GetAncestor(tab_contents()->GetNativeView(),
-                               GA_ROOT);
-  dialog_ = views::Window::CreateChromeWindow(root_hwnd, gfx::Rect(), this);
-  dialog_->Show();
+  gfx::NativeWindow root_hwnd = client()->GetMessageBoxRootWindow();
+  // GetMessageBoxRootWindow() will be NULL if there's no selected tab (e.g.,
+  // during shutdown), in which case we simply skip showing this dialog.
+  if (!root_hwnd) {
+    Cancel();
+  } else {
+    dialog_ = views::Window::CreateChromeWindow(root_hwnd, gfx::Rect(), this);
+    dialog_->Show();
+  }
 }
 
 void JavascriptMessageBoxDialog::ActivateModalDialog() {
@@ -72,13 +77,12 @@ int JavascriptMessageBoxDialog::GetDialogButtons() const {
 }
 
 std::wstring JavascriptMessageBoxDialog::GetWindowTitle() const {
-  return parent_->title();;
+  return parent_->title();
 }
 
 
 void JavascriptMessageBoxDialog::WindowClosing() {
   dialog_ = NULL;
-
 }
 
 void JavascriptMessageBoxDialog::DeleteDelegate() {
diff --git a/chrome/browser/views/jsmessage_box_dialog.h b/chrome/browser/views/jsmessage_box_dialog.h
index f709a50..92a2635 100644
--- a/chrome/browser/views/jsmessage_box_dialog.h
+++ b/chrome/browser/views/jsmessage_box_dialog.h
@@ -11,7 +11,7 @@
 #include "views/window/dialog_delegate.h"
 
 class MessageBoxView;
-class TabContents;
+class JavaScriptMessageBoxClient;
 namespace views {
 class Window;
 }
@@ -47,8 +47,8 @@ class JavascriptMessageBoxDialog : public views::DialogDelegate {
   virtual void OnClose();
 
  private:
-  TabContents* tab_contents() {
-    return parent_->tab_contents();
+  JavaScriptMessageBoxClient* client() {
+    return parent_->client();
   }
 
   // A pointer to the AppModalDialog that owns us.
diff --git a/chrome/chrome.gyp b/chrome/chrome.gyp
index aa8d6d1..7cc828e 100755
--- a/chrome/chrome.gyp
+++ b/chrome/chrome.gyp
@@ -1747,6 +1747,7 @@
         'browser/jankometer.h',
         'browser/jumplist.cc',
         'browser/jumplist.h',
+        'browser/jsmessage_box_client.h',
         'browser/jsmessage_box_handler.cc',
         'browser/jsmessage_box_handler.h',
         'browser/keychain_mac.cc',