Mac: reform our shutdown routine.

chrome/browser/js_modal_dialog_mac.mm

 // 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"
 
 #import <Cocoa/Cocoa.h>
 
 #include "app/l10n_util_mac.h"
 #include "app/message_box_flags.h"
 #import "base/cocoa_protocols_mac.h"
 #include "base/sys_string_conversions.h"
+#import "chrome/browser/chrome_browser_application_mac.h"
 #include "grit/app_strings.h"
 #include "grit/generated_resources.h"
 
 // Helper object that receives the notification that the dialog/sheet is
 // going away. Is responsible for cleaning itself up.
 @interface JavaScriptAppModalDialogHelper : NSObject<NSAlertDelegate> {
  @private
   NSAlert* alert_;
   NSTextField* textField_;  // WEAK; owned by alert_
 }
@@ skipping 38 matching lines @@
     input = base::SysNSStringToWide([textField_ stringValue]);
   switch (returnCode) {
     case NSAlertFirstButtonReturn:  {  // OK
       bool shouldSuppress = false;
       if ([alert showsSuppressionButton])
         shouldSuppress = [[alert suppressionButton] state] == NSOnState;
       bridge->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())
+        chrome_browser_application_mac::CancelTerminate();
+
       bridge->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();
       break;
     }
@@ skipping 91 matching lines @@
   NOTIMPLEMENTED();
   return nil;
 }
 
 void JavaScriptAppModalDialog::CloseModalDialog() {
   NSAlert* alert = dialog_;
   DCHECK([alert isKindOfClass:[NSAlert class]]);
   [NSApp endSheet:[alert window]];
   dialog_ = nil;
 }