[Mac] Implement form resubmission warning dialog

chrome/browser/cocoa/repost_form_warning_mac.mm

Index: chrome/browser/cocoa/repost_form_warning_mac.mm
diff --git a/chrome/browser/cocoa/repost_form_warning_mac.mm b/chrome/browser/cocoa/repost_form_warning_mac.mm
new file mode 100644
index 0000000000000000000000000000000000000000..ab63ceedcdffe493229f2f59bfe7a7c48c1408f1
--- /dev/null
+++ b/chrome/browser/cocoa/repost_form_warning_mac.mm
@@ -0,0 +1,93 @@
+// 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/cocoa/repost_form_warning_mac.h"
+
+#include "app/l10n_util_mac.h"
+#include "base/message_loop.h"
+#include "chrome/browser/tab_contents/navigation_controller.h"
+#include "chrome/common/notification_service.h"
+#include "grit/generated_resources.h"
+
+@implementation RepostDelegate
+- (id)initWithWarning:(RepostFormWarningMac*)warning {
+  if ((self = [super init])) {
+    warning_ = warning;
+  }
+  return self;
+}
+
+- (void)alertDidEnd:(NSAlert*)alert
+         returnCode:(int)returnCode
+        contextInfo:(void*)contextInfo {
+  if (returnCode == NSAlertFirstButtonReturn)
+    warning_->Confirm();
+  else
+    warning_->Cancel();
+}
+@end
+
+RepostFormWarningMac::RepostFormWarningMac(
+    NSWindow* parent,
+    NavigationController* navigation_controller)
+    : navigation_controller_(navigation_controller),
+      alert_([[NSAlert alloc] init]),
+      delegate_([[RepostDelegate alloc] initWithWarning:this]) {
+  [alert_ setMessageText:
+      l10n_util::GetNSStringWithFixup(IDS_HTTP_POST_WARNING_TITLE)];
+  [alert_ setInformativeText:
+      l10n_util::GetNSStringWithFixup(IDS_HTTP_POST_WARNING)];
+  [alert_ addButtonWithTitle:
+      l10n_util::GetNSStringWithFixup(IDS_HTTP_POST_WARNING_RESEND)];
+  [alert_ addButtonWithTitle:
+      l10n_util::GetNSStringWithFixup(IDS_HTTP_POST_WARNING_CANCEL)];
+
+  [alert_ beginSheetModalForWindow:parent
+                    modalDelegate:delegate_.get()
+                   didEndSelector:@selector(alertDidEnd:returnCode:contextInfo:)
+                      contextInfo:nil];
+
+  registrar_.Add(this, NotificationType::LOAD_START,
+                 Source<NavigationController>(navigation_controller_));
+  registrar_.Add(this, NotificationType::TAB_CLOSING,
+                 Source<NavigationController>(navigation_controller_));
+}
+
+RepostFormWarningMac::~RepostFormWarningMac() {
+}
+
+void RepostFormWarningMac::Confirm() {
+  Destroy();
+  if (navigation_controller_)
+    navigation_controller_->Reload(false);
+}
+
+void RepostFormWarningMac::Cancel() {
+  Destroy();
+}
+
+void RepostFormWarningMac::Observe(NotificationType type,
+                                   const NotificationSource& source,
+                                   const NotificationDetails& details) {
+  // Close the dialog if we load a page (because reloading might not apply to
+  // the same page anymore) or if the tab is closed, because then we won't have
+  // a navigation controller anymore.
+  if (alert_ && navigation_controller_ &&
+      (type == NotificationType::LOAD_START ||
+       type == NotificationType::TAB_CLOSING)) {
+    DCHECK_EQ(Source<NavigationController>(source).ptr(),
+              navigation_controller_);
+    navigation_controller_ = NULL;
+
+    // This will call |Cancel()|.
+    [NSApp endSheet:[alert_ window] returnCode:NSAlertSecondButtonReturn];
+  }
+}
+
+void RepostFormWarningMac::Destroy() {
+  if (alert_) {
+    alert_.reset(NULL);
+    MessageLoop::current()->DeleteSoon(FROM_HERE, this);
+  }
+}