Moved |openedByDOM| to WebState's CreateParams and public interface.

ios/web/web_state/ui/crw_web_controller.mm

Index: ios/web/web_state/ui/crw_web_controller.mm
diff --git a/ios/web/web_state/ui/crw_web_controller.mm b/ios/web/web_state/ui/crw_web_controller.mm
index e23141e1fb0ba7a4916fff43a41a8033ca04ef90..c15eb0c28b87b3c90437e3146c956e359006209b 100644
--- a/ios/web/web_state/ui/crw_web_controller.mm
+++ b/ios/web/web_state/ui/crw_web_controller.mm
@@ -436,6 +436,8 @@ @interface CRWWebController ()<CRWContextMenuDelegate,
 @property(nonatomic, readonly) CRWSessionController* sessionController;
 // The associated NavigationManagerImpl.
 @property(nonatomic, readonly) NavigationManagerImpl* navigationManagerImpl;
+// Whether the associated WebState has an opener.
+@property(nonatomic, readonly) BOOL hasOpener;
 // Dictionary where keys are the names of WKWebView properties and values are
 // selector names which should be called when a corresponding property has
 // changed. e.g. @{ @"URL" : @"webViewURLDidChange" } means that
@@ -1864,7 +1866,7 @@ - (void)loadCurrentURL {
       ![_nativeProvider hasControllerForURL:currentURL]) {
     if (!(item->GetTransitionType() & ui::PAGE_TRANSITION_TYPED ||
           item->GetTransitionType() & ui::PAGE_TRANSITION_AUTO_BOOKMARK) &&
-        self.sessionController.openedByDOM) {
+        self.hasOpener) {
       // WebUI URLs can not be opened by DOM to prevent cross-site scripting as
       // they have increased power. WebUI URLs may only be opened when the user
       // types in the URL or use bookmarks.
@@ -2196,7 +2198,7 @@ - (BOOL)shouldClosePageOnNativeApplicationLoad {
   // the page has no navigation items, as occurs when an App Store link is
   // opened from another application.
   BOOL rendererInitiatedWithoutInteraction =
-      self.sessionController.openedByDOM && !_userInteractedWithWebController;
+      self.hasOpener && !_userInteractedWithWebController;
   BOOL noNavigationItems = !(self.navigationManagerImpl->GetItemCount());
   return rendererInitiatedWithoutInteraction || noNavigationItems;
 }
@@ -3473,6 +3475,10 @@ - (NavigationManagerImpl*)navigationManagerImpl {
   return _webStateImpl ? &(_webStateImpl->GetNavigationManagerImpl()) : nil;
 }
 
+- (BOOL)hasOpener {
+  return _webStateImpl ? _webStateImpl->HasOpener() : NO;
+}
+
 - (web::NavigationItemImpl*)currentNavItem {
   // This goes through the legacy Session* interface rather than Navigation*
   // because it is itself a legacy method that should not exist, and this
@@ -4216,8 +4222,7 @@ - (WKWebView*)webView:(WKWebView*)webView
   CRWWebController* childWebController =
       static_cast<WebStateImpl*>(childWebState)->GetWebController();
 
-  DCHECK(!childWebController ||
-         childWebController.sessionController.openedByDOM);
+  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
@@ -4230,9 +4235,8 @@ - (WKWebView*)webView:(WKWebView*)webView
 }
 
 - (void)webViewDidClose:(WKWebView*)webView {
-  if (self.sessionController.openedByDOM) {
+  if (self.hasOpener)
     _webStateImpl->CloseWebState();
-  }
 }
 
 - (void)webView:(WKWebView*)webView