Additional checks/calls for cases when WebUI may be already gone but OOBE screen instance is not

chrome/browser/chromeos/login/mock_network_screen.cc

Index: chrome/browser/chromeos/login/mock_network_screen.cc
diff --git a/chrome/browser/chromeos/login/mock_network_screen.cc b/chrome/browser/chromeos/login/mock_network_screen.cc
index 1ec0d71341089ff75e4d47acce003bb76cd1056d..411de6263d67ddd62749e85275821d32315bcbb3 100644
--- a/chrome/browser/chromeos/login/mock_network_screen.cc
+++ b/chrome/browser/chromeos/login/mock_network_screen.cc
@@ -17,11 +17,19 @@ MockNetworkScreen::MockNetworkScreen(ScreenObserver* observer,
 MockNetworkScreen::~MockNetworkScreen() {
 }
 
+
 MockNetworkScreenActor::MockNetworkScreenActor() {
-  EXPECT_CALL(*this, SetDelegate(NotNull())).Times(AtLeast(1));
+  EXPECT_CALL(*this, MockSetDelegate(NotNull())).Times(AtLeast(1));
 }
 
 MockNetworkScreenActor::~MockNetworkScreenActor() {
+  if (delegate_)
+    delegate_->OnActorDestroyed(this);
+}
+
+void MockNetworkScreenActor::SetDelegate(Delegate* delegate) {
+  delegate_ = delegate;
+  MockSetDelegate(delegate);
 }
 
 }  // namespace chromeos