--- a/dom/events/Event.cpp
+++ b/dom/events/Event.cpp
@@ -172,17 +172,17 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(Ev
         break;
       }
       case NS_CLIPBOARD_EVENT:
         tmp->mEvent->AsClipboardEvent()->clipboardData = nullptr;
         break;
       case NS_MUTATION_EVENT:
         tmp->mEvent->AsMutationEvent()->mRelatedNode = nullptr;
         break;
-      case NS_FOCUS_EVENT:
+      case eFocusEventClass:
         tmp->mEvent->AsFocusEvent()->relatedTarget = nullptr;
         break;
       default:
         break;
     }
   }
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mPresContext);
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mExplicitOriginalTarget);
@@ -215,17 +215,17 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(
       case NS_CLIPBOARD_EVENT:
         NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mEvent->clipboardData");
         cb.NoteXPCOMChild(tmp->mEvent->AsClipboardEvent()->clipboardData);
         break;
       case NS_MUTATION_EVENT:
         NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mEvent->mRelatedNode");
         cb.NoteXPCOMChild(tmp->mEvent->AsMutationEvent()->mRelatedNode);
         break;
-      case NS_FOCUS_EVENT:
+      case eFocusEventClass:
         NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mEvent->relatedTarget");
         cb.NoteXPCOMChild(tmp->mEvent->AsFocusEvent()->relatedTarget);
         break;
       default:
         break;
     }
   }
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPresContext)

--- a/dom/events/EventDispatcher.cpp
+++ b/dom/events/EventDispatcher.cpp
@@ -700,17 +700,17 @@ EventDispatcher::CreateEvent(EventTarget
       return NS_NewDOMKeyboardEvent(aDOMEvent, aOwner, aPresContext,
                                     aEvent->AsKeyboardEvent());
     case eCompositionEventClass:
       return NS_NewDOMCompositionEvent(aDOMEvent, aOwner, aPresContext,
                                        aEvent->AsCompositionEvent());
     case eMouseEventClass:
       return NS_NewDOMMouseEvent(aDOMEvent, aOwner, aPresContext,
                                  aEvent->AsMouseEvent());
-    case NS_FOCUS_EVENT:
+    case eFocusEventClass:
       return NS_NewDOMFocusEvent(aDOMEvent, aOwner, aPresContext,
                                  aEvent->AsFocusEvent());
     case eMouseScrollEventClass:
       return NS_NewDOMMouseScrollEvent(aDOMEvent, aOwner, aPresContext,
                                        aEvent->AsMouseScrollEvent());
     case eWheelEventClass:
       return NS_NewDOMWheelEvent(aDOMEvent, aOwner, aPresContext,
                                  aEvent->AsWheelEvent());

--- a/dom/events/EventNameList.h
+++ b/dom/events/EventNameList.h
@@ -424,25 +424,25 @@ EVENT(beforescriptexecute,
 EVENT(afterscriptexecute,
       NS_AFTER_SCRIPT_EXECUTE,
       EventNameType_HTMLXUL,
       NS_EVENT)
 
 FORWARDED_EVENT(blur,
                 NS_BLUR_CONTENT,
                 EventNameType_HTMLXUL,
-                NS_FOCUS_EVENT)
+                eFocusEventClass)
 ERROR_EVENT(error,
             NS_LOAD_ERROR,
             EventNameType_All,
             NS_EVENT)
 FORWARDED_EVENT(focus,
                 NS_FOCUS_CONTENT,
                 EventNameType_HTMLXUL,
-                NS_FOCUS_EVENT)
+                eFocusEventClass)
 FORWARDED_EVENT(load,
                 NS_LOAD,
                 EventNameType_All,
                 NS_EVENT)
 FORWARDED_EVENT(scroll,
                 NS_SCROLL_EVENT,
                 (EventNameType_HTMLXUL | EventNameType_SVGSVG),
                 NS_EVENT)

--- a/widget/BasicEvents.h
+++ b/widget/BasicEvents.h
@@ -50,17 +50,17 @@ enum EventClassID MOZ_ENUM_TYPE(EventCla
   eGestureNotifyEventClass,          // WidgetGestureNotifyEvent
   eSimpleGestureEventClass,          // WidgetSimpleGestureEvent
   eTouchEventClass,                  // WidgetTouchEvent
 
   // ContentEvents.h
   eScrollPortEventClass,             // InternalScrollPortEvent
   eScrollAreaEventClass,             // InternalScrollAreaEvent
   eFormEventClass,                   // InternalFormEvent
-  NS_FOCUS_EVENT,                    // InternalFocusEvent
+  eFocusEventClass,                  // InternalFocusEvent
   NS_CLIPBOARD_EVENT,                // InternalClipboardEvent
   NS_TRANSITION_EVENT,               // InternalTransitionEvent
   NS_ANIMATION_EVENT,                // InternalAnimationEvent
   NS_SVGZOOM_EVENT,                  // InternalSVGZoomEvent
   NS_SMIL_TIME_EVENT,                // InternalSMILTimeEvent
 
   // MiscEvents.h
   NS_COMMAND_EVENT,                  // WidgetCommandEvent

--- a/widget/ContentEvents.h
+++ b/widget/ContentEvents.h
@@ -189,25 +189,26 @@ public:
  * mozilla::InternalFocusEvent
  ******************************************************************************/
 
 class InternalFocusEvent : public InternalUIEvent
 {
 public:
   virtual InternalFocusEvent* AsFocusEvent() MOZ_OVERRIDE { return this; }
 
-  InternalFocusEvent(bool aIsTrusted, uint32_t aMessage) :
-    InternalUIEvent(aIsTrusted, aMessage, NS_FOCUS_EVENT),
-    fromRaise(false), isRefocus(false)
+  InternalFocusEvent(bool aIsTrusted, uint32_t aMessage)
+    : InternalUIEvent(aIsTrusted, aMessage, eFocusEventClass)
+    , fromRaise(false)
+    , isRefocus(false)
   {
   }
 
   virtual WidgetEvent* Duplicate() const MOZ_OVERRIDE
   {
-    MOZ_ASSERT(mClass == NS_FOCUS_EVENT,
+    MOZ_ASSERT(mClass == eFocusEventClass,
                "Duplicate() must be overridden by sub class");
     InternalFocusEvent* result = new InternalFocusEvent(false, message);
     result->AssignFocusEventData(*this, true);
     result->mFlags = mFlags;
     return result;
   }
 
   /// The possible related target