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

ios/web/webui/web_ui_mojo_inttest.mm

Index: ios/web/webui/web_ui_mojo_inttest.mm
diff --git a/ios/web/webui/web_ui_mojo_inttest.mm b/ios/web/webui/web_ui_mojo_inttest.mm
index cd69059a5afa0a8722a2064b1b0af39f201a861f..d709279c517a370eaca5ade16f4265ec98bc9e6d 100644
--- a/ios/web/webui/web_ui_mojo_inttest.mm
+++ b/ios/web/webui/web_ui_mojo_inttest.mm
@@ -132,10 +132,10 @@ explicit TestWebUIControllerFactory(TestUIHandler* ui_handler)
 // A test fixture for verifying mojo comminication for WebUI.
 class WebUIMojoTest : public WebIntTest {
  protected:
-  WebUIMojoTest()
-      : web_state_(new WebStateImpl(GetBrowserState())),
-        ui_handler_(new TestUIHandler()) {
-    web_state_->GetNavigationManagerImpl().InitializeSession(NO);
+  WebUIMojoTest() : ui_handler_(new TestUIHandler()) {
+    web::WebState::CreateParams params(GetBrowserState());
+    web_state_ = base::MakeUnique<web::WebStateImpl>(params);
+    web_state_->GetNavigationManagerImpl().InitializeSession();
     WebUIIOSControllerFactory::RegisterFactory(
         new TestWebUIControllerFactory(ui_handler_.get()));
   }