Refactor AppModalDialog to more clearly isolate platform specific UI pieces and eliminate the dependency on individual frontends from cross platform code.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/3398015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@60785 0039d316-1c4b-4281-b951-d872f2087c98

22 files changed, 521 insertions, 470 deletions

diff --git a/chrome/browser/app_modal_dialog.cc b/chrome/browser/app_modal_dialog.cc
index 09d1f33..506d76f 100644
--- a/chrome/browser/app_modal_dialog.cc
+++ b/chrome/browser/app_modal_dialog.cc
@@ -5,20 +5,20 @@
 #include "chrome/browser/app_modal_dialog.h"
 
 #include "chrome/browser/app_modal_dialog_queue.h"
+#include "chrome/browser/native_app_modal_dialog.h"
 #include "chrome/browser/tab_contents/tab_contents.h"
 #include "chrome/common/notification_service.h"
 #include "chrome/common/notification_type.h"
 
 AppModalDialog::AppModalDialog(TabContents* tab_contents,
                                const std::wstring& title)
-#if defined(OS_WIN) || defined(OS_LINUX)
-    : dialog_(NULL),
-#elif defined(OS_MACOSX)
-    :
-#endif
+    : skip_this_dialog_(false),
       tab_contents_(tab_contents),
-      title_(title),
-      skip_this_dialog_(false) {
+      native_dialog_(NULL),
+      title_(title) {
+}
+
+AppModalDialog::~AppModalDialog() {
 }
 
 void AppModalDialog::ShowModalDialog() {
@@ -33,11 +33,19 @@ void AppModalDialog::ShowModalDialog() {
       NotificationService::NoDetails());
 }
 
-void AppModalDialog::Cleanup() {
-  NotificationService::current()->Notify(
-      NotificationType::APP_MODAL_DIALOG_CLOSED,
-      Source<AppModalDialog>(this),
-      NotificationService::NoDetails());
+void AppModalDialog::CreateAndShowDialog() {
+  native_dialog_ = CreateNativeDialog();
+  native_dialog_->ShowAppModalDialog();
+}
+
+void AppModalDialog::ActivateModalDialog() {
+  DCHECK(native_dialog_);
+  native_dialog_->ActivateAppModalDialog();
+}
+
+void AppModalDialog::CloseModalDialog() {
+  DCHECK(native_dialog_);
+  native_dialog_->CloseAppModalDialog();
 }
 
 void AppModalDialog::CompleteDialog() {
diff --git a/chrome/browser/app_modal_dialog.h b/chrome/browser/app_modal_dialog.h
index a3bf31a..708e86e 100644
--- a/chrome/browser/app_modal_dialog.h
+++ b/chrome/browser/app_modal_dialog.h
@@ -13,19 +13,7 @@
 #include "chrome/common/notification_observer.h"
 #include "chrome/common/notification_registrar.h"
 
-// Define NativeDialog type as platform specific dialog view.
-#if defined(OS_WIN)
-class ModalDialogDelegate;
-typedef ModalDialogDelegate* NativeDialog;
-#elif defined(OS_MACOSX)
-typedef void* NativeDialog;
-#elif defined(TOOLKIT_USES_GTK)
-typedef struct _GtkDialog GtkDialog;
-typedef struct _GtkWidget GtkWidget;
-typedef int gint;
-typedef GtkWidget* NativeDialog;
-#endif
-
+class NativeAppModalDialog;
 class TabContents;
 
 // A controller+model base class for modal dialogs.
@@ -37,74 +25,57 @@ class AppModalDialog {
   AppModalDialog(TabContents* tab_contents, const std::wstring& title);
   virtual ~AppModalDialog();
 
-  // Called by the app modal window queue when it is time to show this window.
+  // Called by the AppModalDialogQueue to show this dialog.
   void ShowModalDialog();
 
-  // Returns true if the dialog is still valid. As dialogs are created they are
-  // added to the AppModalDialogQueue. When the current modal dialog finishes
-  // and it's time to show the next dialog in the queue IsValid is invoked.
-  // If IsValid returns false the dialog is deleted and not shown.
-  virtual bool IsValid() { return !skip_this_dialog_; }
-
-  /////////////////////////////////////////////////////////////////////////////
-  // The following methods are platform specific and should be implemented in
-  // the platform specific .cc files.
-  // Create the platform specific NativeDialog and display it.  When the
-  // NativeDialog is closed, it should call OnAccept or OnCancel to notify the
-  // renderer of the user's action.  The NativeDialog is also expected to
-  // delete the AppModalDialog associated with it.
-  virtual void CreateAndShowDialog();
-
-#if defined(TOOLKIT_USES_GTK)
-  virtual void HandleDialogResponse(GtkDialog* dialog, gint response_id) = 0;
-  // Callback for dialog response calls, passes results to specialized
-  // HandleDialogResponse() implementation.
-  static void OnDialogResponse(GtkDialog* dialog, gint response_id,
-                               AppModalDialog* app_modal_dialog);
-#endif
-
-  // Close the dialog if it is showing.
-  virtual void CloseModalDialog();
-
-  // Called by the app modal window queue to activate the window.
+  // Called by the AppModalDialogQueue to activate the dialog.
   void ActivateModalDialog();
 
+  // Closes the dialog if it is showing.
+  void CloseModalDialog();
+
   // Completes dialog handling, shows next modal dialog from the queue.
+  // TODO(beng): Get rid of this method.
   void CompleteDialog();
 
   // Dialog window title.
-  std::wstring title() {
-    return title_;
-  }
+  std::wstring title() const { return title_; }
 
-  // Helper methods used to query or control the dialog. This is used by
-  // automation.
-  virtual int GetDialogButtons() = 0;
-  virtual void AcceptWindow() = 0;
-  virtual void CancelWindow() = 0;
+  NativeAppModalDialog* native_dialog() const { return native_dialog_; }
 
- protected:
-  // Cleans up the dialog class.
-  virtual void Cleanup();
-  // Creates the actual platform specific dialog view class.
-  virtual NativeDialog CreateNativeDialog() = 0;
+  // Methods overridable by AppModalDialog subclasses:
 
-  // A reference to the platform native dialog box.
-#if defined(OS_LINUX) || defined(OS_WIN)
-  NativeDialog dialog_;
-#endif
+  // Creates an implementation of NativeAppModalDialog and shows it.
+  // When the native dialog is closed, the implementation of
+  // NativeAppModalDialog should call OnAccept or OnCancel to notify the
+  // renderer of the user's action. The NativeAppModalDialog is also
+  // expected to delete the AppModalDialog associated with it.
+  virtual void CreateAndShowDialog();
 
-  // Parent tab contents.
-  TabContents* tab_contents_;
+  // Returns true if the dialog is still valid. As dialogs are created they are
+  // added to the AppModalDialogQueue. When the current modal dialog finishes
+  // and it's time to show the next dialog in the queue IsValid is invoked.
+  // If IsValid returns false the dialog is deleted and not shown.
+  virtual bool IsValid() { return !skip_this_dialog_; }
 
-  // Information about the message box is held in the following variables.
-  std::wstring title_;
+ protected:
+  // Overridden by subclasses to create the feature-specific native dialog box.
+  virtual NativeAppModalDialog* CreateNativeDialog() = 0;
 
   // 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_;
 
+  // Parent tab contents.
+  TabContents* tab_contents_;
+
  private:
+  // The toolkit-specific implementation of the app modal dialog box.
+  NativeAppModalDialog* native_dialog_;
+
+  // Information about the message box is held in the following variables.
+  std::wstring title_;
+
   DISALLOW_COPY_AND_ASSIGN(AppModalDialog);
 };
 
diff --git a/chrome/browser/app_modal_dialog_gtk.cc b/chrome/browser/app_modal_dialog_gtk.cc
deleted file mode 100644
index 63bcc87..0000000
--- a/chrome/browser/app_modal_dialog_gtk.cc
+++ /dev/null
@@ -1,49 +0,0 @@
-// 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.
-
-#include "chrome/browser/app_modal_dialog.h"
-
-#include <gtk/gtk.h>
-
-#include "base/logging.h"
-#include "base/string_util.h"
-#include "chrome/browser/browser_list.h"
-#include "chrome/browser/browser_window.h"
-#include "chrome/browser/gtk/gtk_util.h"
-#include "chrome/browser/tab_contents/tab_contents.h"
-#include "chrome/browser/tab_contents/tab_contents_view.h"
-#include "grit/generated_resources.h"
-#include "grit/locale_settings.h"
-
-AppModalDialog::~AppModalDialog() {
-}
-
-void AppModalDialog::CreateAndShowDialog() {
-}
-
-// static
-void AppModalDialog::OnDialogResponse(GtkDialog* dialog, gint response_id,
-                                      AppModalDialog* app_modal_dialog) {
-  app_modal_dialog->HandleDialogResponse(dialog, response_id);
-}
-
-void AppModalDialog::ActivateModalDialog() {
-  DCHECK(dialog_);
-  gtk_window_present(GTK_WINDOW(dialog_));
-}
-
-void AppModalDialog::CloseModalDialog() {
-  DCHECK(dialog_);
-  HandleDialogResponse(GTK_DIALOG(dialog_), GTK_RESPONSE_DELETE_EVENT);
-}
-
-void AppModalDialog::AcceptWindow() {
-  DCHECK(dialog_);
-  HandleDialogResponse(GTK_DIALOG(dialog_), GTK_RESPONSE_OK);
-}
-
-void AppModalDialog::CancelWindow() {
-  DCHECK(dialog_);
-  HandleDialogResponse(GTK_DIALOG(dialog_), GTK_RESPONSE_CANCEL);
-}
diff --git a/chrome/browser/app_modal_dialog_mac.mm b/chrome/browser/app_modal_dialog_mac.mm
deleted file mode 100644
index 8d23387..0000000
--- a/chrome/browser/app_modal_dialog_mac.mm
+++ /dev/null
@@ -1,24 +0,0 @@
-// 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/app_modal_dialog.h"
-
-#import <Cocoa/Cocoa.h>
-
-#include "base/logging.h"
-
-AppModalDialog::~AppModalDialog() {
-}
-
-void AppModalDialog::CreateAndShowDialog() {
-  NOTIMPLEMENTED();
-}
-
-void AppModalDialog::ActivateModalDialog() {
-  NOTIMPLEMENTED();
-}
-
-void AppModalDialog::CloseModalDialog() {
-  NOTIMPLEMENTED();
-}
diff --git a/chrome/browser/app_modal_dialog_win.cc b/chrome/browser/app_modal_dialog_win.cc
deleted file mode 100644
index e48d986..0000000
--- a/chrome/browser/app_modal_dialog_win.cc
+++ /dev/null
@@ -1,29 +0,0 @@
-// 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.
-
-#include "chrome/browser/app_modal_dialog.h"
-
-#include "base/logging.h"
-#include "chrome/browser/views/jsmessage_box_dialog.h"
-#include "views/window/dialog_delegate.h"
-#include "views/window/window.h"
-
-AppModalDialog::~AppModalDialog() {
-}
-
-void AppModalDialog::CreateAndShowDialog() {
-  dialog_ = CreateNativeDialog();
-  DCHECK(dialog_->IsModal());
-  dialog_->ShowModalDialog();
-}
-
-void AppModalDialog::ActivateModalDialog() {
-  DCHECK(dialog_);
-  dialog_->ActivateModalDialog();
-}
-
-void AppModalDialog::CloseModalDialog() {
-  DCHECK(dialog_);
-  dialog_->CloseModalDialog();
-}
diff --git a/chrome/browser/automation/testing_automation_provider.cc b/chrome/browser/automation/testing_automation_provider.cc
index 07865e6..29146ec 100644
--- a/chrome/browser/automation/testing_automation_provider.cc
+++ b/chrome/browser/automation/testing_automation_provider.cc
@@ -39,6 +39,7 @@
 #include "chrome/browser/find_bar.h"
 #include "chrome/browser/location_bar.h"
 #include "chrome/browser/login_prompt.h"
+#include "chrome/browser/native_app_modal_dialog.h"
 #include "chrome/browser/profile.h"
 #include "chrome/browser/platform_util.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ -1865,11 +1866,11 @@ void TestingAutomationProvider::SetBooleanPreference(int handle,
 
 void TestingAutomationProvider::GetShowingAppModalDialog(bool* showing_dialog,
                                                          int* dialog_button) {
-  AppModalDialog* dialog_delegate =
-      Singleton<AppModalDialogQueue>()->active_dialog();
-  *showing_dialog = (dialog_delegate != NULL);
+  NativeAppModalDialog* native_dialog =
+      Singleton<AppModalDialogQueue>()->active_dialog()->native_dialog();
+  *showing_dialog = (native_dialog != NULL);
   if (*showing_dialog)
-    *dialog_button = dialog_delegate->GetDialogButtons();
+    *dialog_button = native_dialog->GetAppModalDialogButtons();
   else
     *dialog_button = MessageBoxFlags::DIALOGBUTTON_NONE;
 }
@@ -1878,19 +1879,19 @@ void TestingAutomationProvider::ClickAppModalDialogButton(int button,
                                                           bool* success) {
   *success = false;
 
-  AppModalDialog* dialog_delegate =
-      Singleton<AppModalDialogQueue>()->active_dialog();
-  if (dialog_delegate &&
-      (dialog_delegate->GetDialogButtons() & button) == button) {
+  NativeAppModalDialog* native_dialog =
+      Singleton<AppModalDialogQueue>()->active_dialog()->native_dialog();
+  if (native_dialog &&
+      (native_dialog->GetAppModalDialogButtons() & button) == button) {
     if ((button & MessageBoxFlags::DIALOGBUTTON_OK) ==
         MessageBoxFlags::DIALOGBUTTON_OK) {
-      dialog_delegate->AcceptWindow();
+      native_dialog->AcceptAppModalDialog();
       *success =  true;
     }
     if ((button & MessageBoxFlags::DIALOGBUTTON_CANCEL) ==
         MessageBoxFlags::DIALOGBUTTON_CANCEL) {
       DCHECK(!*success) << "invalid param, OK and CANCEL specified";
-      dialog_delegate->CancelWindow();
+      native_dialog->CancelAppModalDialog();
       *success =  true;
     }
   }
diff --git a/chrome/browser/browser_browsertest.cc b/chrome/browser/browser_browsertest.cc
index fa60fef..1bd9a14 100644
--- a/chrome/browser/browser_browsertest.cc
+++ b/chrome/browser/browser_browsertest.cc
@@ -20,6 +20,7 @@
 #include "chrome/browser/extensions/extension_browsertest.h"
 #include "chrome/browser/extensions/extensions_service.h"
 #include "chrome/browser/js_modal_dialog.h"
+#include "chrome/browser/native_app_modal_dialog.h"
 #include "chrome/browser/profile.h"
 #include "chrome/browser/renderer_host/render_process_host.h"
 #include "chrome/browser/renderer_host/render_view_host.h"
@@ -290,12 +291,12 @@ IN_PROC_BROWSER_TEST_F(BrowserTest, MAYBE_SingleBeforeUnloadAfterWindowClose) {
   browser()->GetTabContentsAt(0)->render_view_host()->
       ExecuteJavascriptInWebFrame(L"", L"w.close(); alert('bar');");
   AppModalDialog* alert = ui_test_utils::WaitForAppModalDialog();
-  alert->AcceptWindow();
+  alert->native_dialog()->AcceptAppModalDialog();
 
   alert = ui_test_utils::WaitForAppModalDialog();
   EXPECT_FALSE(static_cast<JavaScriptAppModalDialog*>(alert)->
                    is_before_unload_dialog());
-  alert->AcceptWindow();
+  alert->native_dialog()->AcceptAppModalDialog();
 }
 
 // Test that get_process_idle_time() returns reasonable values when compared
diff --git a/chrome/browser/chromeos/tab_closeable_state_watcher_browsertest.cc b/chrome/browser/chromeos/tab_closeable_state_watcher_browsertest.cc
index 9b0f997..ea49119 100644
--- a/chrome/browser/chromeos/tab_closeable_state_watcher_browsertest.cc
+++ b/chrome/browser/chromeos/tab_closeable_state_watcher_browsertest.cc
@@ -9,6 +9,7 @@
 #include "chrome/browser/browser.h"
 #include "chrome/browser/browser_list.h"
 #include "chrome/browser/browser_window.h"
+#include "chrome/browser/native_app_modal_dialog.h"
 #include "chrome/browser/profile.h"
 #include "chrome/browser/tab_contents/tab_contents.h"
 #include "chrome/browser/tabs/tab_strip_model.h"
@@ -282,7 +283,7 @@ IN_PROC_BROWSER_TEST_F(TabCloseableStateWatcherTest,
   TabContents* tab_contents = browser()->GetSelectedTabContents();
   browser()->CloseWindow();
   AppModalDialog* confirm = ui_test_utils::WaitForAppModalDialog();
-  confirm->CancelWindow();
+  confirm->native_dialog()->CancelAppModalDialog();
   ui_test_utils::RunAllPendingInMessageLoop();
   EXPECT_EQ(1u, BrowserList::size());
   EXPECT_EQ(browser(), *(BrowserList::begin()));
@@ -292,7 +293,7 @@ IN_PROC_BROWSER_TEST_F(TabCloseableStateWatcherTest,
   // Close the browser.
   browser()->CloseWindow();
   confirm = ui_test_utils::WaitForAppModalDialog();
-  confirm->AcceptWindow();
+  confirm->native_dialog()->AcceptAppModalDialog();
   ui_test_utils::RunAllPendingInMessageLoop();
 }
 
@@ -308,7 +309,7 @@ IN_PROC_BROWSER_TEST_F(TabCloseableStateWatcherTest,
   // Close browser, click OK in BeforeUnload confirm dialog.
   browser()->CloseWindow();
   AppModalDialog* confirm = ui_test_utils::WaitForAppModalDialog();
-  confirm->AcceptWindow();
+  confirm->native_dialog()->AcceptAppModalDialog();
   NewTabObserver new_tab_observer(browser());
   EXPECT_EQ(1u, BrowserList::size());
   EXPECT_EQ(browser(), *(BrowserList::begin()));
diff --git a/chrome/browser/cocoa/js_modal_dialog_cocoa.h b/chrome/browser/cocoa/js_modal_dialog_cocoa.h
new file mode 100644
index 0000000..b31b1c2
--- /dev/null
+++ b/chrome/browser/cocoa/js_modal_dialog_cocoa.h
@@ -0,0 +1,48 @@
+// 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.
+
+#ifndef CHROME_BROWSER_COCOA_JS_MODAL_DIALOG_COCOA_H_
+#define CHROME_BROWSER_COCOA_JS_MODAL_DIALOG_COCOA_H_
+#pragma once
+
+#include "chrome/browser/native_app_modal_dialog.h"
+
+#include "base/logging.h"
+#include "base/scoped_nsobject.h"
+#include "base/scoped_ptr.h"
+
+#if __OBJC__
+@class NSAlert;
+@class JavaScriptAppModalDialogHelper;
+#else
+class NSAlert;
+class JavaScriptAppModalDialogHelper;
+#endif
+
+class JSModalDialogCocoa : public NativeAppModalDialog {
+ public:
+  explicit JSModalDialogCocoa(JavaScriptAppModalDialog* dialog);
+  virtual ~JSModalDialogCocoa();
+
+  // Overridden from NativeAppModalDialog:
+  virtual int GetAppModalDialogButtons() const;
+  virtual void ShowAppModalDialog();
+  virtual void ActivateAppModalDialog();
+  virtual void CloseAppModalDialog();
+  virtual void AcceptAppModalDialog();
+  virtual void CancelAppModalDialog();
+
+  JavaScriptAppModalDialog* dialog() const { return dialog_.get(); }
+
+ private:
+  scoped_ptr<JavaScriptAppModalDialog> dialog_;
+
+  scoped_nsobject<JavaScriptAppModalDialogHelper> helper_;
+  NSAlert* alert_; // weak, owned by |helper_|.
+
+  DISALLOW_COPY_AND_ASSIGN(JSModalDialogCocoa);
+};
+
+#endif  // CHROME_BROWSER_COCOA_JS_MODAL_DIALOG_COCOA_H_
+
diff --git a/chrome/browser/js_modal_dialog_mac.mm b/chrome/browser/cocoa/js_modal_dialog_cocoa.mm
index ca21e55..ced3af1 100644
--- a/chrome/browser/js_modal_dialog_mac.mm
+++ b/chrome/browser/cocoa/js_modal_dialog_cocoa.mm
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "chrome/browser/js_modal_dialog.h"
+#include "chrome/browser/cocoa/js_modal_dialog_cocoa.h"
 
 #import <Cocoa/Cocoa.h>
 
@@ -12,6 +12,7 @@
 #include "base/logging.h"
 #include "base/sys_string_conversions.h"
 #import "chrome/browser/chrome_browser_application_mac.h"
+#include "chrome/browser/js_modal_dialog.h"
 #include "grit/app_strings.h"
 #include "grit/generated_resources.h"
 
@@ -51,13 +52,12 @@
   [super dealloc];
 }
 
-// |contextInfo| is the bridge back to the C++ JavaScriptAppModalDialog. When
-// complete, autorelease to clean ourselves up.
+// |contextInfo| is the JSModalDialogCocoa that owns us.
 - (void)alertDidEnd:(NSAlert*)alert
          returnCode:(int)returnCode
         contextInfo:(void*)contextInfo {
-  JavaScriptAppModalDialog* bridge =
-      reinterpret_cast<JavaScriptAppModalDialog*>(contextInfo);
+  scoped_ptr<JSModalDialogCocoa> native_dialog(
+      reinterpret_cast<JSModalDialogCocoa*>(contextInfo));
   std::wstring input;
   if (textField_)
     input = base::SysNSStringToWide([textField_ stringValue]);
@@ -66,35 +66,38 @@
       bool shouldSuppress = false;
       if ([alert showsSuppressionButton])
         shouldSuppress = [[alert suppressionButton] state] == NSOnState;
-      bridge->OnAccept(input, shouldSuppress);
+      native_dialog->dialog()->OnAccept(input, shouldSuppress);
       break;
     }
     case NSAlertSecondButtonReturn:  {  // Cancel
       // If the user wants to stay on this page, stop quitting (if a quit is in
       // progress).
-      if (bridge->is_before_unload_dialog())
+      if (native_dialog->dialog()->is_before_unload_dialog())
         chrome_browser_application_mac::CancelTerminate();
 
-      bridge->OnCancel();
+      native_dialog->dialog()->OnCancel();
       break;
     }
     case NSRunStoppedResponse: {  // Window was closed underneath us
       // Need to call OnCancel() because there is some cleanup that needs
       // to be done.  It won't call back to the javascript since the
       // JavaScriptAppModalDialog knows that the TabContents was destroyed.
-      bridge->OnCancel();
+      native_dialog->dialog()->OnCancel();
       break;
     }
     default:  {
       NOTREACHED();
     }
   }
-  [self autorelease];
-  delete bridge;  // Done with the dialog, it needs be destroyed.
 }
 @end
 
-void JavaScriptAppModalDialog::CreateAndShowDialog() {
+////////////////////////////////////////////////////////////////////////////////
+// JSModalDialogCocoa, public:
+
+JSModalDialogCocoa::JSModalDialogCocoa(JavaScriptAppModalDialog* dialog)
+    : dialog_(dialog),
+      helper_(NULL) {
   // Determine the names of the dialog buttons based on the flags. "Default"
   // is the OK button. "Other" is the cancel button. We don't use the
   // "Alternate" button in NSRunAlertPanel.
@@ -102,12 +105,12 @@ void JavaScriptAppModalDialog::CreateAndShowDialog() {
   NSString* other_button = l10n_util::GetNSStringWithFixup(IDS_APP_CANCEL);
   bool text_field = false;
   bool one_button = false;
-  switch (dialog_flags_) {
+  switch (dialog_->dialog_flags()) {
     case MessageBoxFlags::kIsJavascriptAlert:
       one_button = true;
       break;
     case MessageBoxFlags::kIsJavascriptConfirm:
-      if (is_before_unload_dialog_) {
+      if (dialog_->is_before_unload_dialog()) {
         default_button = l10n_util::GetNSStringWithFixup(
             IDS_BEFOREUNLOAD_MESSAGEBOX_OK_BUTTON_LABEL);
         other_button = l10n_util::GetNSStringWithFixup(
@@ -125,46 +128,42 @@ void JavaScriptAppModalDialog::CreateAndShowDialog() {
   // Create a helper which will receive the sheet ended selector. It will
   // delete itself when done. It doesn't need anything passed to its init
   // as it will get a contextInfo parameter.
-  JavaScriptAppModalDialogHelper* helper =
-      [[JavaScriptAppModalDialogHelper alloc] init];
+  helper_.reset([[JavaScriptAppModalDialogHelper alloc] init]);
 
   // Show the modal dialog.
-  NSAlert* alert = [helper alert];
-  dialog_ = alert;
+  alert_ = [helper_ alert];
   NSTextField* field = nil;
   if (text_field) {
-    field = [helper textField];
-    [field setStringValue:base::SysWideToNSString(default_prompt_text_)];
+    field = [helper_ textField];
+    [field setStringValue:base::SysWideToNSString(
+        dialog_->default_prompt_text())];
   }
-  [alert setDelegate:helper];
-  [alert setInformativeText:base::SysWideToNSString(message_text_)];
-  [alert setMessageText:base::SysWideToNSString(title_)];
-  [alert addButtonWithTitle:default_button];
+  [alert_ setDelegate:helper_];
+  [alert_ setInformativeText:base::SysWideToNSString(dialog_->message_text())];
+  [alert_ setMessageText:base::SysWideToNSString(dialog_->title())];
+  [alert_ addButtonWithTitle:default_button];
   if (!one_button) {
-    NSButton* other = [alert addButtonWithTitle:other_button];
+    NSButton* other = [alert_ addButtonWithTitle:other_button];
     [other setKeyEquivalent:@"\e"];
   }
-  if (display_suppress_checkbox_) {
-    [alert setShowsSuppressionButton:YES];
+  if (dialog_->display_suppress_checkbox()) {
+    [alert_ setShowsSuppressionButton:YES];
     NSString* suppression_title = l10n_util::GetNSStringWithFixup(
         IDS_JAVASCRIPT_MESSAGEBOX_SUPPRESS_OPTION);
-    [[alert suppressionButton] setTitle:suppression_title];
+    [[alert_ suppressionButton] setTitle:suppression_title];
   }
+}
 
-  [alert beginSheetModalForWindow:nil  // nil here makes it app-modal
-                    modalDelegate:helper
-                   didEndSelector:@selector(alertDidEnd:returnCode:contextInfo:)
-                      contextInfo:this];
-
-  if (field)
-    [[alert window] makeFirstResponder:field];
+JSModalDialogCocoa::~JSModalDialogCocoa() {
 }
 
-// The functions below are used by the automation framework.
-int JavaScriptAppModalDialog::GetDialogButtons() {
+////////////////////////////////////////////////////////////////////////////////
+// JSModalDialogCocoa, NativeAppModalDialog implementation:
+
+int JSModalDialogCocoa::GetAppModalDialogButtons() const {
   // From the above, it is the case that if there is 1 button, it is always the
   // OK button.  The second button, if it exists, is always the Cancel button.
-  int num_buttons = [[dialog_ buttons] count];
+  int num_buttons = [[alert_ buttons] count];
   switch (num_buttons) {
     case 1:
       return MessageBoxFlags::DIALOGBUTTON_OK;
@@ -177,27 +176,43 @@ int JavaScriptAppModalDialog::GetDialogButtons() {
   }
 }
 
-// On Mac, this is only used in testing.
-void JavaScriptAppModalDialog::AcceptWindow() {
-  NSButton* first = [[dialog_ buttons] objectAtIndex:0];
+void JSModalDialogCocoa::ShowAppModalDialog() {
+  [alert_
+      beginSheetModalForWindow:nil  // nil here makes it app-modal
+                 modalDelegate:helper_.get()
+                didEndSelector:@selector(alertDidEnd:returnCode:contextInfo:)
+                   contextInfo:this];
+
+  if ([helper_ textField])
+    [[alert_ window] makeFirstResponder:[helper_ textField]];
+}
+
+void JSModalDialogCocoa::ActivateAppModalDialog() {
+}
+
+void JSModalDialogCocoa::CloseAppModalDialog() {
+  DCHECK([alert_ isKindOfClass:[NSAlert class]]);
+  [NSApp endSheet:[alert_ window]];
+  alert_ = NULL;
+}
+
+void JSModalDialogCocoa::AcceptAppModalDialog() {
+  NSButton* first = [[alert_ buttons] objectAtIndex:0];
   [first performClick:nil];
 }
 
-void JavaScriptAppModalDialog::CancelWindow() {
-  DCHECK([[dialog_ buttons] count] >= 2);
-  NSButton* second = [[dialog_ buttons] objectAtIndex:1];
+void JSModalDialogCocoa::CancelAppModalDialog() {
+  DCHECK([[alert_ buttons] count] >= 2);
+  NSButton* second = [[alert_ buttons] objectAtIndex:1];
   [second performClick:nil];
 }
 
-// This is only used by the app-modal dialog machinery on windows.
-NativeDialog JavaScriptAppModalDialog::CreateNativeDialog() {
-  NOTIMPLEMENTED();
-  return nil;
-}
+////////////////////////////////////////////////////////////////////////////////
+// NativeAppModalDialog, public:
 
-void JavaScriptAppModalDialog::CloseModalDialog() {
-  NSAlert* alert = dialog_;
-  DCHECK([alert isKindOfClass:[NSAlert class]]);
-  [NSApp endSheet:[alert window]];
-  dialog_ = nil;
+// static
+NativeAppModalDialog* NativeAppModalDialog::CreateNativeJavaScriptPrompt(
+    JavaScriptAppModalDialog* dialog,
+    gfx::NativeWindow parent_window) {
+  return new JSModalDialogCocoa(dialog);
 }
diff --git a/chrome/browser/js_modal_dialog_gtk.cc b/chrome/browser/gtk/js_modal_dialog_gtk.cc
index 0c07a3f..9a12cc9 100644
--- a/chrome/browser/js_modal_dialog_gtk.cc
+++ b/chrome/browser/gtk/js_modal_dialog_gtk.cc
@@ -1,8 +1,8 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// 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/js_modal_dialog.h"
+#include "chrome/browser/gtk/js_modal_dialog_gtk.h"
 
 #include <gtk/gtk.h>
 
@@ -12,8 +12,7 @@
 #include "base/logging.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/gtk/gtk_util.h"
-#include "chrome/browser/tab_contents/tab_contents.h"
-#include "chrome/browser/tab_contents/tab_contents_view.h"
+#include "chrome/browser/js_modal_dialog.h"
 #include "grit/generated_resources.h"
 #include "grit/locale_settings.h"
 
@@ -46,76 +45,25 @@ bool ShouldSuppressJSDialogs(GtkDialog* dialog) {
 
 }  // namespace
 
-void JavaScriptAppModalDialog::CreateAndShowDialog() {
-  dialog_ = CreateNativeDialog();
-  gtk_util::ShowModalDialogWithMinLocalizedWidth(GTK_WIDGET(dialog_),
-      IDS_ALERT_DIALOG_WIDTH_CHARS);
-}
-
-void JavaScriptAppModalDialog::HandleDialogResponse(GtkDialog* dialog,
-                                                    gint response_id) {
-  switch (response_id) {
-    case GTK_RESPONSE_OK:
-      // The first arg is the prompt text and the second is true if we want to
-      // suppress additional popups from the page.
-      OnAccept(GetPromptText(dialog), ShouldSuppressJSDialogs(dialog));
-      break;
-
-    case GTK_RESPONSE_CANCEL:
-    case GTK_RESPONSE_DELETE_EVENT:   // User hit the X on the dialog.
-      OnCancel();
-      break;
-
-    default:
-      NOTREACHED();
-  }
-  gtk_widget_destroy(GTK_WIDGET(dialog));
+////////////////////////////////////////////////////////////////////////////////
+// JSModalDialogGtk, public:
 
-  // Now that the dialog is gone, we can put all the  windows into separate
-  // window groups so other dialogs are no longer app modal.
-  gtk_util::AppModalDismissedUngroupWindows();
-  delete this;
-}
-
-int JavaScriptAppModalDialog::GetDialogButtons() {
-  switch (dialog_flags_) {
-    case MessageBoxFlags::kIsJavascriptAlert:
-      return MessageBoxFlags::DIALOGBUTTON_OK;
-
-    case MessageBoxFlags::kIsJavascriptConfirm:
-      return MessageBoxFlags::DIALOGBUTTON_OK |
-             MessageBoxFlags::DIALOGBUTTON_CANCEL;
-
-    case MessageBoxFlags::kIsJavascriptPrompt:
-      return MessageBoxFlags::DIALOGBUTTON_OK;
-
-    default:
-      NOTREACHED();
-      return 0;
-  }
-}
-
-void JavaScriptAppModalDialog::AcceptWindow() {
-  HandleDialogResponse(GTK_DIALOG(dialog_), GTK_RESPONSE_OK);
-}
-
-void JavaScriptAppModalDialog::CancelWindow() {
-  HandleDialogResponse(GTK_DIALOG(dialog_), GTK_RESPONSE_CANCEL);
-}
-
-NativeDialog JavaScriptAppModalDialog::CreateNativeDialog() {
+JSModalDialogGtk::JSModalDialogGtk(JavaScriptAppModalDialog* dialog,
+                                   gfx::NativeWindow parent_window)
+    : dialog_(dialog) {
   GtkButtonsType buttons = GTK_BUTTONS_NONE;
   GtkMessageType message_type = GTK_MESSAGE_OTHER;
+
   // We add in the OK button manually later because we want to focus it
   // explicitly.
-  switch (dialog_flags_) {
+  switch (dialog_->dialog_flags()) {
     case MessageBoxFlags::kIsJavascriptAlert:
       buttons = GTK_BUTTONS_NONE;
       message_type = GTK_MESSAGE_WARNING;
       break;
 
     case MessageBoxFlags::kIsJavascriptConfirm:
-      if (is_before_unload_dialog_) {
+      if (dialog_->is_before_unload_dialog()) {
         // onbeforeunload also uses a confirm prompt, it just has custom
         // buttons.  We add the buttons using gtk_dialog_add_button below.
         buttons = GTK_BUTTONS_NONE;
@@ -138,56 +86,149 @@ NativeDialog JavaScriptAppModalDialog::CreateNativeDialog() {
   // same window group.
   gtk_util::MakeAppModalWindowGroup();
 
-  gfx::NativeWindow window = client_->GetMessageBoxRootWindow();
-  NativeDialog dialog = gtk_message_dialog_new(window, GTK_DIALOG_MODAL,
-      message_type, buttons, "%s", WideToUTF8(message_text_).c_str());
-  gtk_util::ApplyMessageDialogQuirks(dialog);
-  gtk_window_set_title(GTK_WINDOW(dialog), WideToUTF8(title_).c_str());
+  gtk_dialog_ = gtk_message_dialog_new(parent_window,
+      GTK_DIALOG_MODAL, message_type, buttons, "%s",
+      WideToUTF8(dialog_->message_text()).c_str());
+  gtk_util::ApplyMessageDialogQuirks(gtk_dialog_);
+  gtk_window_set_title(GTK_WINDOW(gtk_dialog_),
+                       WideToUTF8(dialog_->title()).c_str());
 
   // Adjust content area as needed.  Set up the prompt text entry or
   // suppression check box.
-  if (MessageBoxFlags::kIsJavascriptPrompt == dialog_flags_) {
+  if (MessageBoxFlags::kIsJavascriptPrompt == dialog_->dialog_flags()) {
     // TODO(tc): Replace with gtk_dialog_get_content_area() when using GTK 2.14+
-    GtkWidget* contents_vbox = GTK_DIALOG(dialog)->vbox;
+    GtkWidget* contents_vbox = GTK_DIALOG(gtk_dialog_)->vbox;
     GtkWidget* text_box = gtk_entry_new();
     gtk_entry_set_text(GTK_ENTRY(text_box),
-                       WideToUTF8(default_prompt_text_).c_str());
+        WideToUTF8(dialog_->default_prompt_text()).c_str());
     gtk_box_pack_start(GTK_BOX(contents_vbox), text_box, TRUE, TRUE, 0);
-    g_object_set_data(G_OBJECT(dialog), kPromptTextId, text_box);
+    g_object_set_data(G_OBJECT(gtk_dialog_), kPromptTextId, text_box);
     gtk_entry_set_activates_default(GTK_ENTRY(text_box), TRUE);
   }
 
-  if (display_suppress_checkbox_) {
-    GtkWidget* contents_vbox = GTK_DIALOG(dialog)->vbox;
+  if (dialog_->display_suppress_checkbox()) {
+    GtkWidget* contents_vbox = GTK_DIALOG(gtk_dialog_)->vbox;
     GtkWidget* check_box = gtk_check_button_new_with_label(
         l10n_util::GetStringUTF8(
-            IDS_JAVASCRIPT_MESSAGEBOX_SUPPRESS_OPTION).c_str());
+        IDS_JAVASCRIPT_MESSAGEBOX_SUPPRESS_OPTION).c_str());
     gtk_box_pack_start(GTK_BOX(contents_vbox), check_box, TRUE, TRUE, 0);
-    g_object_set_data(G_OBJECT(dialog), kSuppressCheckboxId, check_box);
+    g_object_set_data(G_OBJECT(gtk_dialog_), kSuppressCheckboxId, check_box);
   }
 
   // Adjust buttons/action area as needed.
-  if (is_before_unload_dialog_) {
+  if (dialog_->is_before_unload_dialog()) {
     std::string button_text = l10n_util::GetStringUTF8(
-        IDS_BEFOREUNLOAD_MESSAGEBOX_OK_BUTTON_LABEL);
-    gtk_dialog_add_button(GTK_DIALOG(dialog), button_text.c_str(),
-                          GTK_RESPONSE_OK);
+      IDS_BEFOREUNLOAD_MESSAGEBOX_OK_BUTTON_LABEL);
+    gtk_dialog_add_button(GTK_DIALOG(gtk_dialog_), button_text.c_str(),
+        GTK_RESPONSE_OK);
 
     button_text = l10n_util::GetStringUTF8(
         IDS_BEFOREUNLOAD_MESSAGEBOX_CANCEL_BUTTON_LABEL);
-    gtk_dialog_add_button(GTK_DIALOG(dialog), button_text.c_str(),
-                          GTK_RESPONSE_CANCEL);
+    gtk_dialog_add_button(GTK_DIALOG(gtk_dialog_), button_text.c_str(),
+        GTK_RESPONSE_CANCEL);
   } else {
     // Add the OK button and focus it.
-    GtkWidget* ok_button = gtk_dialog_add_button(GTK_DIALOG(dialog),
+    GtkWidget* ok_button = gtk_dialog_add_button(GTK_DIALOG(gtk_dialog_),
         GTK_STOCK_OK, GTK_RESPONSE_OK);
-    if (MessageBoxFlags::kIsJavascriptPrompt != dialog_flags_)
+    if (MessageBoxFlags::kIsJavascriptPrompt != dialog_->dialog_flags())
       gtk_widget_grab_focus(ok_button);
   }
 
-  gtk_dialog_set_default_response(GTK_DIALOG(dialog), GTK_RESPONSE_OK);
-  g_signal_connect(dialog, "response",
-                   G_CALLBACK(AppModalDialog::OnDialogResponse),
-                   reinterpret_cast<AppModalDialog*>(this));
-  return dialog;
+  gtk_dialog_set_default_response(GTK_DIALOG(gtk_dialog_), GTK_RESPONSE_OK);
+  g_signal_connect(gtk_dialog_, "response",
+      G_CALLBACK(JSModalDialogGtk::OnDialogResponse),
+      reinterpret_cast<JSModalDialogGtk*>(this));
+}
+
+JSModalDialogGtk::~JSModalDialogGtk() {
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// JSModalDialogGtk, NativeAppModalDialog implementation:
+
+int JSModalDialogGtk::GetAppModalDialogButtons() const {
+  switch (dialog_->dialog_flags()) {
+    case MessageBoxFlags::kIsJavascriptAlert:
+      return MessageBoxFlags::DIALOGBUTTON_OK;
+
+    case MessageBoxFlags::kIsJavascriptConfirm:
+      return MessageBoxFlags::DIALOGBUTTON_OK |
+        MessageBoxFlags::DIALOGBUTTON_CANCEL;
+
+    case MessageBoxFlags::kIsJavascriptPrompt:
+      return MessageBoxFlags::DIALOGBUTTON_OK;
+
+    default:
+      NOTREACHED();
+      return 0;
+  }
+}
+
+void JSModalDialogGtk::ShowAppModalDialog() {
+  gtk_util::ShowModalDialogWithMinLocalizedWidth(GTK_WIDGET(gtk_dialog_),
+      IDS_ALERT_DIALOG_WIDTH_CHARS);
+}
+
+void JSModalDialogGtk::ActivateAppModalDialog() {
+  DCHECK(gtk_dialog_);
+  gtk_window_present(GTK_WINDOW(gtk_dialog_));}
+
+void JSModalDialogGtk::CloseAppModalDialog() {
+  DCHECK(gtk_dialog_);
+  HandleDialogResponse(GTK_DIALOG(gtk_dialog_), GTK_RESPONSE_DELETE_EVENT);
+}
+
+void JSModalDialogGtk::AcceptAppModalDialog() {
+  HandleDialogResponse(GTK_DIALOG(gtk_dialog_), GTK_RESPONSE_OK);
 }
+
+void JSModalDialogGtk::CancelAppModalDialog() {
+  HandleDialogResponse(GTK_DIALOG(gtk_dialog_), GTK_RESPONSE_CANCEL);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// JSModalDialogGtk, private:
+
+void JSModalDialogGtk::HandleDialogResponse(GtkDialog* dialog,
+                                            gint response_id) {
+  switch (response_id) {
+    case GTK_RESPONSE_OK:
+      // The first arg is the prompt text and the second is true if we want to
+      // suppress additional popups from the page.
+      dialog_->OnAccept(GetPromptText(dialog), ShouldSuppressJSDialogs(dialog));
+      break;
+
+    case GTK_RESPONSE_CANCEL:
+    case GTK_RESPONSE_DELETE_EVENT:   // User hit the X on the dialog.
+      dialog_->OnCancel();
+      break;
+
+    default:
+      NOTREACHED();
+  }
+  gtk_widget_destroy(GTK_WIDGET(dialog));
+
+  // Now that the dialog is gone, we can put all the  windows into separate
+  // window groups so other dialogs are no longer app modal.
+  gtk_util::AppModalDismissedUngroupWindows();
+  delete this;
+}
+
+// static
+void JSModalDialogGtk::OnDialogResponse(GtkDialog* gtk_dialog,
+                                        gint response_id,
+                                        JSModalDialogGtk* dialog) {
+  dialog->HandleDialogResponse(gtk_dialog, response_id);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// NativeAppModalDialog, public:
+
+// static
+NativeAppModalDialog* NativeAppModalDialog::CreateNativeJavaScriptPrompt(
+    JavaScriptAppModalDialog* dialog,
+    gfx::NativeWindow parent_window) {
+  return new JSModalDialogGtk(dialog, parent_window);
+}
+
+
diff --git a/chrome/browser/gtk/js_modal_dialog_gtk.h b/chrome/browser/gtk/js_modal_dialog_gtk.h
new file mode 100644
index 0000000..18d573c
--- /dev/null
+++ b/chrome/browser/gtk/js_modal_dialog_gtk.h
@@ -0,0 +1,45 @@
+// 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.
+
+#ifndef CHROME_BROWSER_GTK_JS_MODAL_DIALOG_GTK_H_
+#define CHROME_BROWSER_GTK_JS_MODAL_DIALOG_GTK_H_
+#pragma once
+
+#include <gtk/gtk.h>
+
+#include "app/gtk_signal.h"
+#include "base/logging.h"
+#include "base/scoped_ptr.h"
+#include "chrome/browser/native_app_modal_dialog.h"
+#include "gfx/native_widget_types.h"
+
+class JavaScriptAppModalDialog;
+
+class JSModalDialogGtk : public NativeAppModalDialog {
+ public:
+  JSModalDialogGtk(JavaScriptAppModalDialog* dialog,
+                   gfx::NativeWindow parent_window);
+  virtual ~JSModalDialogGtk();
+
+  // Overridden from NativeAppModalDialog:
+  virtual int GetAppModalDialogButtons() const;
+  virtual void ShowAppModalDialog();
+  virtual void ActivateAppModalDialog();
+  virtual void CloseAppModalDialog();
+  virtual void AcceptAppModalDialog();
+  virtual void CancelAppModalDialog();
+
+ private:
+  void HandleDialogResponse(GtkDialog* dialog, gint response_id);
+  static void OnDialogResponse(GtkDialog* gtk_dialog, gint response_id,
+                               JSModalDialogGtk* dialog);
+
+  scoped_ptr<JavaScriptAppModalDialog> dialog_;
+  GtkWidget* gtk_dialog_;
+
+  DISALLOW_COPY_AND_ASSIGN(JSModalDialogGtk);
+};
+
+#endif  // CHROME_BROWSER_GTK_JS_MODAL_DIALOG_GTK_H_
+
diff --git a/chrome/browser/js_modal_dialog.cc b/chrome/browser/js_modal_dialog.cc
index 7c42c71..8f79da2 100644
--- a/chrome/browser/js_modal_dialog.cc
+++ b/chrome/browser/js_modal_dialog.cc
@@ -7,6 +7,7 @@
 #include "base/string_util.h"
 #include "chrome/browser/browser_shutdown.h"
 #include "chrome/browser/extensions/extension_host.h"
+#include "chrome/browser/native_app_modal_dialog.h"
 #include "chrome/browser/tab_contents/tab_contents.h"
 #include "chrome/common/notification_service.h"
 #include "chrome/common/notification_type.h"
@@ -30,9 +31,6 @@ JavaScriptAppModalDialog::JavaScriptAppModalDialog(
     bool is_before_unload_dialog,
     IPC::Message* reply_msg)
     : AppModalDialog(client->AsTabContents(), title),
-#if defined(OS_MACOSX)
-      dialog_(NULL),
-#endif
       client_(client),
       extension_host_(client->AsExtensionHost()),
       dialog_flags_(dialog_flags),
@@ -52,6 +50,14 @@ JavaScriptAppModalDialog::JavaScriptAppModalDialog(
 JavaScriptAppModalDialog::~JavaScriptAppModalDialog() {
 }
 
+NativeAppModalDialog* JavaScriptAppModalDialog::CreateNativeDialog() {
+  gfx::NativeWindow parent_window = tab_contents_ ?
+      tab_contents_->GetMessageBoxRootWindow() :
+      extension_host_->GetMessageBoxRootWindow();
+  return NativeAppModalDialog::CreateNativeJavaScriptPrompt(this,
+                                                            parent_window);
+}
+
 void JavaScriptAppModalDialog::Observe(NotificationType type,
                                        const NotificationSource& source,
                                        const NotificationDetails& details) {
@@ -68,7 +74,7 @@ void JavaScriptAppModalDialog::Observe(NotificationType type,
   // Also clear the client, since it's now invalid.
   skip_this_dialog_ = true;
   client_ = NULL;
-  if (dialog_)
+  if (native_dialog_)
     CloseModalDialog();
 }
 
@@ -144,5 +150,4 @@ void JavaScriptAppModalDialog::Cleanup() {
       NOTREACHED();
 #endif
   }
-  AppModalDialog::Cleanup();
 }
diff --git a/chrome/browser/js_modal_dialog.h b/chrome/browser/js_modal_dialog.h
index 7cfe34f..b2cccff 100644
--- a/chrome/browser/js_modal_dialog.h
+++ b/chrome/browser/js_modal_dialog.h
@@ -13,16 +13,9 @@
 #include "chrome/common/notification_observer.h"
 #include "chrome/common/notification_registrar.h"
 
-#if defined(OS_MACOSX)
-#if __OBJC__
-@class NSAlert;
-#else
-class NSAlert;
-#endif
-#endif
-
 class ExtensionHost;
 class JavaScriptMessageBoxClient;
+class NativeAppModalDialog;
 
 namespace IPC {
 class Message;
@@ -46,41 +39,27 @@ class JavaScriptAppModalDialog : public AppModalDialog,
   virtual ~JavaScriptAppModalDialog();
 
   // AppModalDialog overrides.
-#if defined(OS_POSIX)
-  virtual void CreateAndShowDialog();
-#endif
-#if defined(TOOLKIT_USES_GTK)
-  virtual void HandleDialogResponse(GtkDialog* dialog, gint response_id);
-#endif
-  virtual int GetDialogButtons();
-  virtual void AcceptWindow();
-  virtual void CancelWindow();
+  virtual NativeAppModalDialog* CreateNativeDialog();
 
   /////////////////////////////////////////////////////////////////////////////
   // Getters so NativeDialog can get information about the message box.
-  JavaScriptMessageBoxClient* client() {
-    return client_;
-  }
-  int dialog_flags() {
-    return dialog_flags_;
-  }
-  bool is_before_unload_dialog() {
-    return is_before_unload_dialog_;
-  }
-
-#if defined(OS_MACOSX)
-  virtual void CloseModalDialog();
-#endif
+  JavaScriptMessageBoxClient* client() const { return client_; }
 
   // Callbacks from NativeDialog when the user accepts or cancels the dialog.
   void OnCancel();
   void OnAccept(const std::wstring& prompt_text, bool suppress_js_messages);
   void OnClose();
 
+  // Accessors
+  int dialog_flags() const { return dialog_flags_; }
+  std::wstring message_text() const { return message_text_; }
+  std::wstring default_prompt_text() const { return default_prompt_text_; }
+  bool display_suppress_checkbox() const { return display_suppress_checkbox_; }
+  bool is_before_unload_dialog() const { return is_before_unload_dialog_; }
+
  protected:
   // AppModalDialog overrides.
   virtual void Cleanup();
-  virtual NativeDialog CreateNativeDialog();
 
  private:
   // NotificationObserver implementation.
@@ -91,9 +70,7 @@ class JavaScriptAppModalDialog : public AppModalDialog,
   // Initializes for notifications to listen.
   void InitNotifications();
 
-#if defined(OS_MACOSX)
-  NSAlert* dialog_;
-#endif
+  NativeAppModalDialog* native_dialog_;
 
   NotificationRegistrar registrar_;
 
diff --git a/chrome/browser/js_modal_dialog_win.cc b/chrome/browser/js_modal_dialog_win.cc
deleted file mode 100644
index 26cebc4..0000000
--- a/chrome/browser/js_modal_dialog_win.cc
+++ /dev/null
@@ -1,30 +0,0 @@
-// 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/js_modal_dialog.h"
-
-#include "chrome/browser/views/jsmessage_box_dialog.h"
-#include "chrome/browser/tab_contents/tab_contents.h"
-#include "views/window/window.h"
-
-int JavaScriptAppModalDialog::GetDialogButtons() {
-  return dialog_->GetDialogButtons();
-}
-
-void JavaScriptAppModalDialog::AcceptWindow() {
-  views::DialogClientView* client_view =
-      dialog_->window()->GetClientView()->AsDialogClientView();
-  client_view->AcceptWindow();
-}
-
-void JavaScriptAppModalDialog::CancelWindow() {
-  views::DialogClientView* client_view =
-      dialog_->window()->GetClientView()->AsDialogClientView();
-  client_view->CancelWindow();
-}
-
-NativeDialog JavaScriptAppModalDialog::CreateNativeDialog() {
-  return new JavaScriptMessageBoxDialog(this, message_text_,
-      default_prompt_text_, display_suppress_checkbox_);
-}
diff --git a/chrome/browser/message_box_handler.cc b/chrome/browser/message_box_handler.cc
index a6006dc..7389cc7 100644
--- a/chrome/browser/message_box_handler.cc
+++ b/chrome/browser/message_box_handler.cc
@@ -24,39 +24,41 @@
 #include "grit/chromium_strings.h"
 
 static std::wstring GetTitle(Profile* profile,
-                             ExtensionsService* extensions_service,
                              bool is_alert,
                              const GURL& frame_url) {
-  Extension* extension = extensions_service->GetExtensionByURL(frame_url);
-  if (!extension)
-    extension = extensions_service->GetExtensionByWebExtent(frame_url);
+  ExtensionsService* extensions_service = profile->GetExtensionsService();
+  if (extensions_service) {
+    Extension* extension = extensions_service->GetExtensionByURL(frame_url);
+    if (!extension)
+      extension = extensions_service->GetExtensionByWebExtent(frame_url);
 
-  if (extension && (extension->location() == Extension::COMPONENT)) {
-    return l10n_util::GetString(IDS_PRODUCT_NAME);
-  } else if (extension && !extension->name().empty()) {
-    return UTF8ToWide(extension->name());
-  } else {
-    if (!frame_url.has_host())
-      return l10n_util::GetString(
-          is_alert ? IDS_JAVASCRIPT_ALERT_DEFAULT_TITLE
-                   : IDS_JAVASCRIPT_MESSAGEBOX_DEFAULT_TITLE);
+    if (extension && (extension->location() == Extension::COMPONENT)) {
+      return l10n_util::GetString(IDS_PRODUCT_NAME);
+    } else if (extension && !extension->name().empty()) {
+      return UTF8ToWide(extension->name());
+    }
+  }
+  if (!frame_url.has_host()) {
+    return l10n_util::GetString(
+        is_alert ? IDS_JAVASCRIPT_ALERT_DEFAULT_TITLE
+                 : IDS_JAVASCRIPT_MESSAGEBOX_DEFAULT_TITLE);
+  }
 
-    // TODO(brettw) it should be easier than this to do the correct language
-    // handling without getting the accept language from the profile.
-    string16 base_address = WideToUTF16(gfx::ElideUrl(frame_url.GetOrigin(),
-          gfx::Font(), 0,
-          UTF8ToWide(
-            profile->GetPrefs()->GetString(prefs::kAcceptLanguages))));
+  // TODO(brettw) it should be easier than this to do the correct language
+  // handling without getting the accept language from the profile.
+  string16 base_address = WideToUTF16(gfx::ElideUrl(frame_url.GetOrigin(),
+      gfx::Font(), 0,
+      UTF8ToWide(
+          profile->GetPrefs()->GetString(prefs::kAcceptLanguages))));
 
-    // Force URL to have LTR directionality.
-    base_address = base::i18n::GetDisplayStringInLTRDirectionality(
-        base_address);
+  // Force URL to have LTR directionality.
+  base_address = base::i18n::GetDisplayStringInLTRDirectionality(
+      base_address);
 
-    return UTF16ToWide(l10n_util::GetStringFUTF16(
-        is_alert ? IDS_JAVASCRIPT_ALERT_TITLE :
-                   IDS_JAVASCRIPT_MESSAGEBOX_TITLE,
-        base_address));
-  }
+  return UTF16ToWide(l10n_util::GetStringFUTF16(
+      is_alert ? IDS_JAVASCRIPT_ALERT_TITLE :
+                 IDS_JAVASCRIPT_MESSAGEBOX_TITLE,
+      base_address));
 }
 
 void RunJavascriptMessageBox(Profile* profile,
@@ -67,13 +69,8 @@ void RunJavascriptMessageBox(Profile* profile,
                              const std::wstring& default_prompt_text,
                              bool display_suppress_checkbox,
                              IPC::Message* reply_msg) {
-  ExtensionsService* extensions_service = profile->GetExtensionsService();
-  if (!extensions_service)
-    return;
-
   bool is_alert = dialog_flags == MessageBoxFlags::kIsJavascriptAlert;
-  std::wstring title = GetTitle(profile, extensions_service,
-                                is_alert, frame_url);
+  std::wstring title = GetTitle(profile, is_alert, frame_url);
   Singleton<AppModalDialogQueue>()->AddDialog(new JavaScriptAppModalDialog(
       client, title, dialog_flags, message_text, default_prompt_text,
       display_suppress_checkbox, false, reply_msg));
diff --git a/chrome/browser/native_app_modal_dialog.h b/chrome/browser/native_app_modal_dialog.h
new file mode 100644
index 0000000..7b4c5b2
--- /dev/null
+++ b/chrome/browser/native_app_modal_dialog.h
@@ -0,0 +1,39 @@
+// 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.
+
+#ifndef CHROME_BROWSER_NATIVE_APP_MODAL_DIALOG_H_
+#define CHROME_BROWSER_NATIVE_APP_MODAL_DIALOG_H_
+#pragma once
+
+#include "gfx/native_widget_types.h"
+
+class JavaScriptAppModalDialog;
+
+class NativeAppModalDialog {
+ public:
+  // Returns the buttons to be shown. See MessageBoxFlags for a description of
+  // the values.
+  virtual int GetAppModalDialogButtons() const = 0;
+
+  // Shows the dialog.
+  virtual void ShowAppModalDialog() = 0;
+
+  // Activates the dialog.
+  virtual void ActivateAppModalDialog() = 0;
+
+  // Closes the dialog.
+  virtual void CloseAppModalDialog() = 0;
+
+  // Accepts or cancels the dialog.
+  virtual void AcceptAppModalDialog() = 0;
+  virtual void CancelAppModalDialog() = 0;
+
+  // Creates an app modal dialog for a JavaScript prompt.
+  static NativeAppModalDialog* CreateNativeJavaScriptPrompt(
+      JavaScriptAppModalDialog* dialog,
+      gfx::NativeWindow parent_window);
+};
+
+#endif  // CHROME_BROWSER_NATIVE_APP_MODAL_DIALOG_H_
+
diff --git a/chrome/browser/views/jsmessage_box_dialog.cc b/chrome/browser/views/jsmessage_box_dialog.cc
index f51116b..c0a6b3a 100644
--- a/chrome/browser/views/jsmessage_box_dialog.cc
+++ b/chrome/browser/views/jsmessage_box_dialog.cc
@@ -8,25 +8,24 @@
 #include "app/l10n_util.h"
 #include "app/message_box_flags.h"
 #include "chrome/browser/app_modal_dialog.h"
-#include "chrome/browser/tab_contents/tab_contents.h"
 #include "grit/generated_resources.h"
 #include "views/controls/message_box_view.h"
 #include "views/window/window.h"
 
+////////////////////////////////////////////////////////////////////////////////
+// JavaScriptMessageBoxDialog, public:
+
 JavaScriptMessageBoxDialog::JavaScriptMessageBoxDialog(
-    JavaScriptAppModalDialog* parent,
-    const std::wstring& message_text,
-    const std::wstring& default_prompt_text,
-    bool display_suppress_checkbox)
+    JavaScriptAppModalDialog* parent)
     : parent_(parent),
       message_box_view_(new MessageBoxView(
           parent->dialog_flags() | MessageBoxFlags::kAutoDetectAlignment,
-          message_text, default_prompt_text)) {
+          parent->message_text(), parent->default_prompt_text())) {
   DCHECK(message_box_view_);
 
   message_box_view_->AddAccelerator(
       views::Accelerator(app::VKEY_C, false, true, false));
-  if (display_suppress_checkbox) {
+  if (parent->display_suppress_checkbox()) {
     message_box_view_->SetCheckBoxLabel(
         l10n_util::GetString(IDS_JAVASCRIPT_MESSAGEBOX_SUPPRESS_OPTION));
   }
@@ -35,8 +34,32 @@ JavaScriptMessageBoxDialog::JavaScriptMessageBoxDialog(
 JavaScriptMessageBoxDialog::~JavaScriptMessageBoxDialog() {
 }
 
-gfx::NativeWindow JavaScriptMessageBoxDialog::GetDialogRootWindow() {
-  return client()->GetMessageBoxRootWindow();
+////////////////////////////////////////////////////////////////////////////////
+// JavaScriptMessageBoxDialog, NativeAppModalDialog implementation:
+
+int JavaScriptMessageBoxDialog::GetAppModalDialogButtons() const {
+  return GetDialogButtons();
+}
+
+void JavaScriptMessageBoxDialog::ShowAppModalDialog() {
+  window()->Show();
+}
+
+void JavaScriptMessageBoxDialog::ActivateAppModalDialog() {
+  window()->Show();
+  window()->Activate();
+}
+
+void JavaScriptMessageBoxDialog::CloseAppModalDialog() {
+  window()->Close();
+}
+
+void JavaScriptMessageBoxDialog::AcceptAppModalDialog() {
+  GetDialogClientView()->AcceptWindow();
+}
+
+void JavaScriptMessageBoxDialog::CancelAppModalDialog() {
+  GetDialogClientView()->CancelWindow();
 }
 
 //////////////////////////////////////////////////////////////////////////////
@@ -116,3 +139,15 @@ views::View* JavaScriptMessageBoxDialog::GetInitiallyFocusedView() {
     return message_box_view_->text_box();
   return views::DialogDelegate::GetInitiallyFocusedView();
 }
+
+////////////////////////////////////////////////////////////////////////////////
+// NativeAppModalDialog, public:
+
+// static
+NativeAppModalDialog* NativeAppModalDialog::CreateNativeJavaScriptPrompt(
+    JavaScriptAppModalDialog* dialog,
+    gfx::NativeWindow parent_window) {
+  JavaScriptMessageBoxDialog* d = new JavaScriptMessageBoxDialog(dialog);
+  views::Window::CreateChromeWindow(parent_window, gfx::Rect(), d);
+  return d;
+}
diff --git a/chrome/browser/views/jsmessage_box_dialog.h b/chrome/browser/views/jsmessage_box_dialog.h
index 512f2cf..08f3dab 100644
--- a/chrome/browser/views/jsmessage_box_dialog.h
+++ b/chrome/browser/views/jsmessage_box_dialog.h
@@ -12,24 +12,26 @@
 
 #include "app/message_box_flags.h"
 #include "chrome/browser/jsmessage_box_client.h"
-#include "chrome/browser/views/modal_dialog_delegate.h"
+#include "chrome/browser/native_app_modal_dialog.h"
+#include "views/window/dialog_delegate.h"
 
 class MessageBoxView;
-class JavaScriptMessageBoxClient;
 
-class JavaScriptMessageBoxDialog : public ModalDialogDelegate {
+class JavaScriptMessageBoxDialog : public NativeAppModalDialog,
+                                   public views::DialogDelegate {
  public:
-  JavaScriptMessageBoxDialog(JavaScriptAppModalDialog* parent,
-                             const std::wstring& message_text,
-                             const std::wstring& default_prompt_text,
-                             bool display_suppress_checkbox);
-
+  explicit JavaScriptMessageBoxDialog(JavaScriptAppModalDialog* parent);
   virtual ~JavaScriptMessageBoxDialog();
 
-  // Overriden from ModalDialogDelegate:
-  virtual gfx::NativeWindow GetDialogRootWindow();
+  // Overridden from NativeAppModalDialog:
+  virtual int GetAppModalDialogButtons() const;
+  virtual void ShowAppModalDialog();
+  virtual void ActivateAppModalDialog();
+  virtual void CloseAppModalDialog();
+  virtual void AcceptAppModalDialog();
+  virtual void CancelAppModalDialog();
 
-  // Overriden from views::DialogDelegate:
+  // Overridden from views::DialogDelegate:
   virtual int GetDefaultDialogButton() const;
   virtual int GetDialogButtons() const;
   virtual std::wstring GetWindowTitle() const;
@@ -40,16 +42,14 @@ class JavaScriptMessageBoxDialog : public ModalDialogDelegate {
   virtual std::wstring GetDialogButtonLabel(
       MessageBoxFlags::DialogButton button) const;
 
-  // Overriden from views::WindowDelegate:
+  // Overridden from views::WindowDelegate:
   virtual bool IsModal() const { return true; }
   virtual views::View* GetContentsView();
   virtual views::View* GetInitiallyFocusedView();
   virtual void OnClose();
 
  private:
-  JavaScriptMessageBoxClient* client() {
-    return parent_->client();
-  }
+  JavaScriptMessageBoxClient* client() const { return parent_->client(); }
 
   // A pointer to the AppModalDialog that owns us.
   JavaScriptAppModalDialog* parent_;
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index 27f8180..7575488 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -73,9 +73,6 @@
         'browser/app_launched_animation.h',
         'browser/app_modal_dialog.cc',
         'browser/app_modal_dialog.h',
-        'browser/app_modal_dialog_gtk.cc',
-        'browser/app_modal_dialog_mac.mm',
-        'browser/app_modal_dialog_win.cc',
         'browser/app_modal_dialog_queue.cc',
         'browser/app_modal_dialog_queue.h',
         'browser/appcache/appcache_dispatcher_host.cc',
@@ -985,6 +982,8 @@
         'browser/cocoa/infobar_test_helper.h',
         'browser/cocoa/install_from_dmg.h',
         'browser/cocoa/install_from_dmg.mm',
+        'browser/cocoa/js_modal_dialog_cocoa.h',
+        'browser/cocoa/js_modal_dialog_cocoa.mm',
         'browser/cocoa/keystone_glue.h',
         'browser/cocoa/keystone_glue.mm',
         'browser/cocoa/keystone_infobar.h',
@@ -1765,6 +1764,8 @@
         'browser/gtk/infobar_container_gtk.h',
         'browser/gtk/infobar_gtk.cc',
         'browser/gtk/infobar_gtk.h',
+        'browser/gtk/js_modal_dialog_gtk.cc',
+        'browser/gtk/js_modal_dialog_gtk.h',
         'browser/gtk/keyword_editor_view.cc',
         'browser/gtk/keyword_editor_view.h',
         'browser/gtk/location_bar_view_gtk.cc',
@@ -2033,9 +2034,6 @@
         'browser/jumplist_win.h',
         'browser/js_modal_dialog.cc',
         'browser/js_modal_dialog.h',
-        'browser/js_modal_dialog_gtk.cc',
-        'browser/js_modal_dialog_mac.mm',
-        'browser/js_modal_dialog_win.cc',
         'browser/jsmessage_box_client.h',
         'browser/keychain_mac.cc',
         'browser/keychain_mac.h',
@@ -2087,6 +2085,7 @@
         'browser/nacl_host/nacl_broker_service_win.h',
         'browser/nacl_host/nacl_process_host.cc',
         'browser/nacl_host/nacl_process_host.h',
+        'browser/native_app_modal_dialog.h',
         'browser/net/blob_url_request_job_factory.cc',
         'browser/net/blob_url_request_job_factory.h',
         'browser/net/browser_url_util.cc',
@@ -3641,6 +3640,8 @@
                 ['include', '^browser/views/info_bubble.h'],
                 ['include', '^browser/views/html_dialog_view.cc'],
                 ['include', '^browser/views/html_dialog_view.h'],
+                ['include', '^browser/views/jsmessage_box_dialog.cc'],
+                ['include', '^browser/views/jsmessage_box_dialog.h'],
                 ['include', '^browser/views/location_bar/click_handler.cc'],
                 ['include', '^browser/views/location_bar/click_handler.h'],
                 ['include', '^browser/views/location_bar/content_setting_image_view.cc'],
diff --git a/chrome/common/notification_type.h b/chrome/common/notification_type.h
index c90d54a..541aaa9 100644
--- a/chrome/common/notification_type.h
+++ b/chrome/common/notification_type.h
@@ -294,10 +294,6 @@ class NotificationType {
     // is the dialog.
     APP_MODAL_DIALOG_SHOWN,
 
-    // Sent after an application-modal dialog has been closed. The source
-    // is the dialog.
-    APP_MODAL_DIALOG_CLOSED,
-
     // Tabs --------------------------------------------------------------------
 
     // Sent when a tab is added to a TabContentsDelegate. The source is the
diff --git a/views/window/window_gtk.cc b/views/window/window_gtk.cc
index 16444b3d9..785b1bc 100644
--- a/views/window/window_gtk.cc
+++ b/views/window/window_gtk.cc
@@ -491,6 +491,8 @@ void WindowGtk::SizeWindowToDefault(GtkWindow* parent) {
 void WindowGtk::OnDestroy(GtkWidget* widget) {
   non_client_view_->WindowClosing();
   WidgetGtk::OnDestroy(widget);
+  window_delegate_->DeleteDelegate();
+  window_delegate_ = NULL;
 }
 
 }  // namespace views