Improve dialog titles generated by embedded pages.

ios/chrome/browser/ui/dialogs/dialog_presenter.mm

 // Copyright 2015 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.
 
 #import "ios/chrome/browser/ui/dialogs/dialog_presenter.h"
 
 #include <deque>
 #include <map>
 
 #import "base/ios/block_types.h"
@@ skipping 13 matching lines @@
 #include "url/gurl.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 // Externed accessibility identifier.
 NSString* const kJavaScriptDialogTextFieldAccessibiltyIdentifier =
     @"JavaScriptDialogTextFieldAccessibiltyIdentifier";
 
-namespace {
-// The hostname to use for JavaScript alerts when there is no valid hostname in
-// the URL passed to |+localizedTitleForJavaScriptAlertFromPage:type:|.
-const char kAboutNullHostname[] = "about:null";
-}  // namespace
-
 @interface DialogPresenter () {
   // Queue of WebStates which correspond to the keys in
   // |_dialogCoordinatorsForWebStates|.
   std::deque<web::WebState*> _queuedWebStates;
   // A map associating queued webStates with their coordinators.
   std::map<web::WebState*, base::scoped_nsobject<AlertCoordinator>>
       _dialogCoordinatorsForWebStates;
 }
 
 // The delegate passed on initialization.
@@ skipping 290 matching lines @@
   // displayed.
   if (self.blockingConfirmationCoordinator)
     return;
   // The active TabModel can't be changed while a JavaScript dialog is shown.
   DCHECK(!self.showingDialog);
   if (_active && !_queuedWebStates.empty() && !self.delegate.presenting)
     [self showNextDialog];
 }
 
 + (NSString*)localizedTitleForJavaScriptAlertFromPage:(const GURL&)pageURL {
+  NSString* localizedTitle = nil;
   NSString* hostname = base::SysUTF8ToNSString(pageURL.host());
-  if (!hostname.length)
-    hostname = base::SysUTF8ToNSString(kAboutNullHostname);
-  return l10n_util::GetNSStringF(IDS_JAVASCRIPT_MESSAGEBOX_TITLE,
-                                 base::SysNSStringToUTF16(hostname));
+  if (!hostname.length) {

[Eugene But (OOO till 7-30), 2017/06/22 20:19:12]

Other platforms use IDS_JAVASCRIPT_MESSAGEBOX_TITLE_NONSTANDARD_URL_IFRAME when
dialog is requested by iframe, not when hostname is empty. Can we follow the
same logic as other platforms?:

bool is_same_origin_as_main_frame =
      (web_contents->GetURL().GetOrigin() == origin_url.GetOrigin());

ios has web_state instead of web_contents, but everything else can be the same.

+    localizedTitle = l10n_util::GetNSString(
+        IDS_JAVASCRIPT_MESSAGEBOX_TITLE_NONSTANDARD_URL_IFRAME);
+  } else {
+    localizedTitle = l10n_util::GetNSStringF(
+        IDS_JAVASCRIPT_MESSAGEBOX_TITLE, base::SysNSStringToUTF16(hostname));
+  }
+  return localizedTitle;
 }
 
 #pragma mark - Private methods.
 
 - (void)addDialogCoordinator:(AlertCoordinator*)coordinator
                  forWebState:(web::WebState*)webState {
   DCHECK(coordinator);
   DCHECK(webState);
   DCHECK_NE(webState, self.presentedDialogWebState);
   DCHECK(!_dialogCoordinatorsForWebStates[webState]);
@@ skipping 134 matching lines @@
                                         style:UIAlertActionStyleDestructive];
     [confirmationCoordinator addItemWithTitle:l10n_util::GetNSString(IDS_CANCEL)
                                        action:cancelHandler
                                         style:UIAlertActionStyleCancel];
     [weakSelf setBlockingConfirmationCoordinator:confirmationCoordinator];
     [[weakSelf blockingConfirmationCoordinator] start];
   } copy];
 }
 
 @end