Provide default implementations for NotificationDelegate methods.

chrome/browser/chromeos/policy/consumer_enrollment_handler.cc

Index: chrome/browser/chromeos/policy/consumer_enrollment_handler.cc
diff --git a/chrome/browser/chromeos/policy/consumer_enrollment_handler.cc b/chrome/browser/chromeos/policy/consumer_enrollment_handler.cc
index aa1238ebe66f8089ef8151fb1eb8e607b2532f6a..97c297095e620b89cfbebeb92dbb723a1032cd0f 100644
--- a/chrome/browser/chromeos/policy/consumer_enrollment_handler.cc
+++ b/chrome/browser/chromeos/policy/consumer_enrollment_handler.cc
@@ -75,11 +75,7 @@ class DesktopNotificationDelegate : public NotificationDelegate {
 
   // NotificationDelegate:
   virtual std::string id() const override;
-  virtual void Display() override;
   virtual void ButtonClick(int button_index) override;
-  virtual void Error() override;
-  virtual void Close(bool by_user) override;
-  virtual void Click() override;
 
  private:
   virtual ~DesktopNotificationDelegate();
@@ -103,22 +99,10 @@ std::string DesktopNotificationDelegate::id() const {
   return id_;
 }
 
-void DesktopNotificationDelegate::Display() {
-}
-
 void DesktopNotificationDelegate::ButtonClick(int button_index) {
   button_click_callback_.Run();
 }
 
-void DesktopNotificationDelegate::Error() {
-}
-
-void DesktopNotificationDelegate::Close(bool by_user) {
-}
-
-void DesktopNotificationDelegate::Click() {
-}
-
 }  // namespace
 
 namespace policy {