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 199b341d988e8f1f163d987ac72d22312fe1f674..7cbab69e411e6653a2b2182887695a8558b53dab 100644
--- a/ios/web/web_state/ui/crw_web_controller.mm
+++ b/ios/web/web_state/ui/crw_web_controller.mm
@@ -1929,7 +1929,7 @@ - (void)loadCurrentURL {
       ![_nativeProvider hasControllerForURL:currentURL]) {
     if (!(item->GetTransitionType() & ui::PAGE_TRANSITION_TYPED ||
           item->GetTransitionType() & ui::PAGE_TRANSITION_AUTO_BOOKMARK) &&
-        self.sessionController.openedByDOM) {
+        self.webState && self.webState->IsOpenedByDOM()) {
       // 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.
@@ -2304,8 +2304,9 @@ - (BOOL)shouldClosePageOnNativeApplicationLoad {
   // no user interaction with the page since the web view was created, or if
   // the page has no navigation items, as occurs when an App Store link is
   // opened from another application.
-  BOOL rendererInitiatedWithoutInteraction =
-      self.sessionController.openedByDOM && !_userInteractedWithWebController;
+  BOOL rendererInitiatedWithoutInteraction = self.webState &&
+                                             self.webState->IsOpenedByDOM() &&
+                                             !_userInteractedWithWebController;
   BOOL noNavigationItems = !(self.navigationManagerImpl->GetItemCount());
   return rendererInitiatedWithoutInteraction || noNavigationItems;
 }
@@ -4335,8 +4336,8 @@ - (WKWebView*)webView:(WKWebView*)webView
   CRWWebController* childWebController =
       static_cast<WebStateImpl*>(childWebState)->GetWebController();
 
-  DCHECK(!childWebController ||
-         childWebController.sessionController.openedByDOM);
+  DCHECK(!childWebController || (childWebController.webState &&
+                                 childWebController.webState->IsOpenedByDOM()));
 
   // WKWebView requires WKUIDelegate to return a child view created with
   // exactly the same |configuration| object (exception is raised if config is
@@ -4349,9 +4350,8 @@ - (WKWebView*)webView:(WKWebView*)webView
 }
 
 - (void)webViewDidClose:(WKWebView*)webView {
-  if (self.sessionController.openedByDOM) {
+  if (self.webState && self.webState->IsOpenedByDOM())
     _webStateImpl->CloseWebState();
-  }
 }
 
 - (void)webView:(WKWebView*)webView