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

ios/web/navigation/navigation_manager_impl.mm

Index: ios/web/navigation/navigation_manager_impl.mm
diff --git a/ios/web/navigation/navigation_manager_impl.mm b/ios/web/navigation/navigation_manager_impl.mm
index bf3c484e69ad9ae44f435fc96276505ca243c9d0..5beaaeb7f9050ef367d86639453512d97997a82b 100644
--- a/ios/web/navigation/navigation_manager_impl.mm
+++ b/ios/web/navigation/navigation_manager_impl.mm
@@ -97,10 +97,9 @@ bool AreURLsInPageNavigation(const GURL& existing_url, const GURL& new_url) {
   [session_controller_ setNavigationManager:this];
 }
 
-void NavigationManagerImpl::InitializeSession(BOOL opened_by_dom) {
-  SetSessionController([[CRWSessionController alloc]
-      initWithBrowserState:browser_state_
-               openedByDOM:opened_by_dom]);
+void NavigationManagerImpl::InitializeSession() {
+  SetSessionController(
+      [[CRWSessionController alloc] initWithBrowserState:browser_state_]);
 }
 
 void NavigationManagerImpl::ReplaceSessionHistory(