Form submission with blank target is broken.

ios/web/web_state/ui/crw_web_controller.mm

 // Copyright 2012 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/web/web_state/ui/crw_web_controller.h"
 
 #import <WebKit/WebKit.h>
 
 #import <objc/runtime.h>
 #include <stddef.h>
@@ skipping 4197 matching lines @@
     DLOG(WARNING) << "Unable to open a window with invalid URL: "
                   << requestURL.spec();
     return nil;
   }
 
   NSString* referrer = [self referrerFromNavigationAction:action];
   GURL openerURL =
       referrer.length ? GURL(base::SysNSStringToUTF8(referrer)) : _documentURL;
 
   WebState* childWebState = _webStateImpl->CreateNewWebState(
-      requestURL, openerURL, [self userIsInteracting]);
+      requestURL, openerURL, [self userClickedRecently]);

[Eugene But (OOO till 7-30), 2017/03/22 00:59:38]

This will allow more popups from malicious pages, so I would be very cautious
about this change. CL descriptions says that "window.open code expects that user
is still interacting with the page", but I don't think that's true.
|userIsInteracting| name is just misleading, it's not doing what it says :(

Current code seems to work correctly with window.open and target="_blank" links.
It does not work correctly with forms. Do you know what is the difference
between "form" case vs. "_blank" links f.e?

   if (!childWebState)
     return nil;
 
   CRWWebController* childWebController =
       static_cast<WebStateImpl*>(childWebState)->GetWebController();
 
   DCHECK(!childWebController || childWebController.hasOpener);
 
   // WKWebView requires WKUIDelegate to return a child view created with
   // exactly the same |configuration| object (exception is raised if config is
@@ skipping 846 matching lines @@
 - (void)simulateLoadRequestWithURL:(const GURL&)URL {
   _lastRegisteredRequestURL = URL;
   _loadPhase = web::LOAD_REQUESTED;
 }
 
 - (NSString*)referrerFromNavigationAction:(WKNavigationAction*)action {
   return [action.request valueForHTTPHeaderField:kReferrerHeaderName];
 }
 
 @end