diff --git a/dom/events/Event.cpp b/dom/events/Event.cpp
index 1658154cff1e..4533e8d05366 100644
--- a/dom/events/Event.cpp
+++ b/dom/events/Event.cpp
@@ -161,7 +161,7 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(Event)
       case eMouseEventClass:
       case eMouseScrollEventClass:
       case eWheelEventClass:
-      case NS_SIMPLE_GESTURE_EVENT:
+      case eSimpleGestureEventClass:
       case ePointerEventClass:
         tmp->mEvent->AsMouseEventBase()->relatedTarget = nullptr;
         break;
@@ -199,7 +199,7 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(Event)
       case eMouseEventClass:
       case eMouseScrollEventClass:
       case eWheelEventClass:
-      case NS_SIMPLE_GESTURE_EVENT:
+      case eSimpleGestureEventClass:
       case ePointerEventClass:
         NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mEvent->relatedTarget");
         cb.NoteXPCOMChild(tmp->mEvent->AsMouseEventBase()->relatedTarget);
@@ -853,7 +853,7 @@ Event::GetScreenCoords(nsPresContext* aPresContext,
         aEvent->mClass != ePointerEventClass &&
         aEvent->mClass != NS_TOUCH_EVENT &&
         aEvent->mClass != eDragEventClass &&
-        aEvent->mClass != NS_SIMPLE_GESTURE_EVENT)) {
+        aEvent->mClass != eSimpleGestureEventClass)) {
     return nsIntPoint(0, 0);
   }
 
@@ -909,7 +909,7 @@ Event::GetClientCoords(nsPresContext* aPresContext,
        aEvent->mClass != NS_TOUCH_EVENT &&
        aEvent->mClass != eDragEventClass &&
        aEvent->mClass != ePointerEventClass &&
-       aEvent->mClass != NS_SIMPLE_GESTURE_EVENT) ||
+       aEvent->mClass != eSimpleGestureEventClass) ||
       !aPresContext ||
       !aEvent->AsGUIEvent()->widget) {
     return aDefaultPoint;
diff --git a/dom/events/EventDispatcher.cpp b/dom/events/EventDispatcher.cpp
index dc54c737af9d..1fa7b448ff6f 100644
--- a/dom/events/EventDispatcher.cpp
+++ b/dom/events/EventDispatcher.cpp
@@ -735,7 +735,7 @@ EventDispatcher::CreateEvent(EventTarget* aOwner,
     case NS_COMMAND_EVENT:
       return NS_NewDOMCommandEvent(aDOMEvent, aOwner, aPresContext,
                                    aEvent->AsCommandEvent());
-    case NS_SIMPLE_GESTURE_EVENT:
+    case eSimpleGestureEventClass:
       return NS_NewDOMSimpleGestureEvent(aDOMEvent, aOwner, aPresContext,
                                          aEvent->AsSimpleGestureEvent());
     case ePointerEventClass:
diff --git a/dom/events/EventNameList.h b/dom/events/EventNameList.h
index 00ebc78e9a8e..3261c8784c96 100644
--- a/dom/events/EventNameList.h
+++ b/dom/events/EventNameList.h
@@ -822,63 +822,63 @@ NON_IDL_EVENT(gamepaddisconnected,
 NON_IDL_EVENT(MozSwipeGestureStart,
               NS_SIMPLE_GESTURE_SWIPE_START,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozSwipeGestureUpdate,
               NS_SIMPLE_GESTURE_SWIPE_UPDATE,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozSwipeGestureEnd,
               NS_SIMPLE_GESTURE_SWIPE_END,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozSwipeGesture,
               NS_SIMPLE_GESTURE_SWIPE,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozMagnifyGestureStart,
               NS_SIMPLE_GESTURE_MAGNIFY_START,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozMagnifyGestureUpdate,
               NS_SIMPLE_GESTURE_MAGNIFY_UPDATE,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozMagnifyGesture,
               NS_SIMPLE_GESTURE_MAGNIFY,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozRotateGestureStart,
               NS_SIMPLE_GESTURE_ROTATE_START,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozRotateGestureUpdate,
               NS_SIMPLE_GESTURE_ROTATE_UPDATE,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozRotateGesture,
               NS_SIMPLE_GESTURE_ROTATE,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozTapGesture,
               NS_SIMPLE_GESTURE_TAP,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozPressTapGesture,
               NS_SIMPLE_GESTURE_PRESSTAP,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozEdgeUIStarted,
               NS_SIMPLE_GESTURE_EDGE_STARTED,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozEdgeUICanceled,
               NS_SIMPLE_GESTURE_EDGE_CANCELED,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 NON_IDL_EVENT(MozEdgeUICompleted,
               NS_SIMPLE_GESTURE_EDGE_COMPLETED,
               EventNameType_None,
-              NS_SIMPLE_GESTURE_EVENT)
+              eSimpleGestureEventClass)
 
 NON_IDL_EVENT(transitionend,
               NS_TRANSITION_END,
diff --git a/dom/events/MouseEvent.cpp b/dom/events/MouseEvent.cpp
index 89df1da3a542..315abcded3c2 100644
--- a/dom/events/MouseEvent.cpp
+++ b/dom/events/MouseEvent.cpp
@@ -75,7 +75,7 @@ MouseEvent::InitMouseEvent(const nsAString& aType,
     case eWheelEventClass:
     case eDragEventClass:
     case ePointerEventClass:
-    case NS_SIMPLE_GESTURE_EVENT: {
+    case eSimpleGestureEventClass: {
       WidgetMouseEventBase* mouseEventBase = mEvent->AsMouseEventBase();
       mouseEventBase->relatedTarget = aRelatedTarget;
       mouseEventBase->button = aButton;
@@ -129,7 +129,7 @@ MouseEvent::InitMouseEvent(const nsAString& aType,
     case eWheelEventClass:
     case eDragEventClass:
     case ePointerEventClass:
-    case NS_SIMPLE_GESTURE_EVENT:
+    case eSimpleGestureEventClass:
       mEvent->AsInputEvent()->modifiers = modifiers;
       return NS_OK;
     default:
@@ -160,7 +160,7 @@ MouseEvent::Constructor(const GlobalObject& aGlobal,
     case eWheelEventClass:
     case eDragEventClass:
     case ePointerEventClass:
-    case NS_SIMPLE_GESTURE_EVENT:
+    case eSimpleGestureEventClass:
       e->mEvent->AsMouseEventBase()->buttons = aParam.mButtons;
       break;
     default:
@@ -219,7 +219,7 @@ MouseEvent::Button()
     case eWheelEventClass:
     case eDragEventClass:
     case ePointerEventClass:
-    case NS_SIMPLE_GESTURE_EVENT:
+    case eSimpleGestureEventClass:
       return mEvent->AsMouseEventBase()->button;
     default:
       NS_WARNING("Tried to get mouse button for non-mouse event!");
@@ -244,7 +244,7 @@ MouseEvent::Buttons()
     case eWheelEventClass:
     case eDragEventClass:
     case ePointerEventClass:
-    case NS_SIMPLE_GESTURE_EVENT:
+    case eSimpleGestureEventClass:
       return mEvent->AsMouseEventBase()->buttons;
     default:
       MOZ_CRASH("Tried to get mouse buttons for non-mouse event!");
@@ -269,7 +269,7 @@ MouseEvent::GetRelatedTarget()
     case eWheelEventClass:
     case eDragEventClass:
     case ePointerEventClass:
-    case NS_SIMPLE_GESTURE_EVENT:
+    case eSimpleGestureEventClass:
       relatedTarget =
         do_QueryInterface(mEvent->AsMouseEventBase()->relatedTarget);
       break;
diff --git a/dom/events/SimpleGestureEvent.cpp b/dom/events/SimpleGestureEvent.cpp
index f3d6747da443..2c81c4057c7b 100644
--- a/dom/events/SimpleGestureEvent.cpp
+++ b/dom/events/SimpleGestureEvent.cpp
@@ -17,7 +17,7 @@ SimpleGestureEvent::SimpleGestureEvent(EventTarget* aOwner,
                aEvent ? aEvent :
                         new WidgetSimpleGestureEvent(false, 0, nullptr))
 {
-  NS_ASSERTION(mEvent->mClass == NS_SIMPLE_GESTURE_EVENT,
+  NS_ASSERTION(mEvent->mClass == eSimpleGestureEventClass,
                "event type mismatch");
 
   if (aEvent) {
diff --git a/dom/events/UIEvent.cpp b/dom/events/UIEvent.cpp
index 8f414e7f40ae..0a298ca29132 100644
--- a/dom/events/UIEvent.cpp
+++ b/dom/events/UIEvent.cpp
@@ -123,7 +123,7 @@ UIEvent::GetMovementPoint()
        mEvent->mClass != eWheelEventClass &&
        mEvent->mClass != eDragEventClass &&
        mEvent->mClass != ePointerEventClass &&
-       mEvent->mClass != NS_SIMPLE_GESTURE_EVENT) ||
+       mEvent->mClass != eSimpleGestureEventClass) ||
        !mEvent->AsGUIEvent()->widget) {
     return nsIntPoint(0, 0);
   }
@@ -302,7 +302,7 @@ UIEvent::GetLayerPoint() const
        mEvent->mClass != ePointerEventClass &&
        mEvent->mClass != NS_TOUCH_EVENT &&
        mEvent->mClass != eDragEventClass &&
-       mEvent->mClass != NS_SIMPLE_GESTURE_EVENT) ||
+       mEvent->mClass != eSimpleGestureEventClass) ||
       !mPresContext ||
       mEventIsInternal) {
     return mLayerPoint;
diff --git a/dom/events/UIEvent.h b/dom/events/UIEvent.h
index 4e821e153c35..876d9baecd0d 100644
--- a/dom/events/UIEvent.h
+++ b/dom/events/UIEvent.h
@@ -48,7 +48,7 @@ public:
          aEvent->mClass != eWheelEventClass &&
          aEvent->mClass != eDragEventClass &&
          aEvent->mClass != ePointerEventClass &&
-         aEvent->mClass != NS_SIMPLE_GESTURE_EVENT)) {
+         aEvent->mClass != eSimpleGestureEventClass)) {
       return nsIntPoint(0, 0);
     }
 
@@ -75,7 +75,7 @@ public:
          aEvent->mClass != eWheelEventClass &&
          aEvent->mClass != eDragEventClass &&
          aEvent->mClass != ePointerEventClass &&
-         aEvent->mClass != NS_SIMPLE_GESTURE_EVENT) ||
+         aEvent->mClass != eSimpleGestureEventClass) ||
         !aPresContext ||
         !aEvent->AsGUIEvent()->widget) {
       return aDefaultClientPoint
diff --git a/dom/xbl/nsXBLEventHandler.cpp b/dom/xbl/nsXBLEventHandler.cpp
index be5fbf84299d..f8585cb2caaa 100644
--- a/dom/xbl/nsXBLEventHandler.cpp
+++ b/dom/xbl/nsXBLEventHandler.cpp
@@ -153,7 +153,7 @@ NS_NewXBLEventHandler(nsXBLPrototypeHandler* aHandler,
     case eMouseEventClass:
     case eMouseScrollEventClass:
     case eWheelEventClass:
-    case NS_SIMPLE_GESTURE_EVENT:
+    case eSimpleGestureEventClass:
       *aResult = new nsXBLMouseEventHandler(aHandler);
       break;
     default:
diff --git a/layout/base/nsLayoutUtils.cpp b/layout/base/nsLayoutUtils.cpp
index 618177338791..17c0b8e19d7f 100644
--- a/layout/base/nsLayoutUtils.cpp
+++ b/layout/base/nsLayoutUtils.cpp
@@ -1873,7 +1873,7 @@ nsLayoutUtils::GetEventCoordinatesRelativeTo(const WidgetEvent* aEvent,
                   aEvent->mClass != eMouseScrollEventClass &&
                   aEvent->mClass != eWheelEventClass &&
                   aEvent->mClass != eDragEventClass &&
-                  aEvent->mClass != NS_SIMPLE_GESTURE_EVENT &&
+                  aEvent->mClass != eSimpleGestureEventClass &&
                   aEvent->mClass != ePointerEventClass &&
                   aEvent->mClass != eGestureNotifyEventClass &&
                   aEvent->mClass != NS_TOUCH_EVENT &&
diff --git a/widget/BasicEvents.h b/widget/BasicEvents.h
index d2fd0a132765..a3141ae2fe58 100644
--- a/widget/BasicEvents.h
+++ b/widget/BasicEvents.h
@@ -48,7 +48,7 @@ enum EventClassID MOZ_ENUM_TYPE(EventClassIDType)
 
   // TouchEvents.h
   eGestureNotifyEventClass,          // WidgetGestureNotifyEvent
-  NS_SIMPLE_GESTURE_EVENT,           // WidgetSimpleGestureEvent
+  eSimpleGestureEventClass,          // WidgetSimpleGestureEvent
   NS_TOUCH_EVENT,                    // WidgetTouchEvent
 
   // ContentEvents.h
diff --git a/widget/TouchEvents.h b/widget/TouchEvents.h
index eee92e2fc2d5..fef7f51ea04a 100644
--- a/widget/TouchEvents.h
+++ b/widget/TouchEvents.h
@@ -97,7 +97,7 @@ public:
   WidgetSimpleGestureEvent(bool aIsTrusted, uint32_t aMessage,
                            nsIWidget* aWidget)
     : WidgetMouseEventBase(aIsTrusted, aMessage, aWidget,
-                           NS_SIMPLE_GESTURE_EVENT)
+                           eSimpleGestureEventClass)
     , allowedDirections(0)
     , direction(0)
     , delta(0.0)
@@ -107,7 +107,7 @@ public:
 
   WidgetSimpleGestureEvent(const WidgetSimpleGestureEvent& aOther)
     : WidgetMouseEventBase(aOther.mFlags.mIsTrusted, aOther.message,
-                           aOther.widget, NS_SIMPLE_GESTURE_EVENT)
+                           aOther.widget, eSimpleGestureEventClass)
     , allowedDirections(aOther.allowedDirections)
     , direction(aOther.direction)
     , delta(aOther.delta)
@@ -117,7 +117,7 @@ public:
 
   virtual WidgetEvent* Duplicate() const MOZ_OVERRIDE
   {
-    MOZ_ASSERT(mClass == NS_SIMPLE_GESTURE_EVENT,
+    MOZ_ASSERT(mClass == eSimpleGestureEventClass,
                "Duplicate() must be overridden by sub class");
     // Not copying widget, it is a weak reference.
     WidgetSimpleGestureEvent* result =
diff --git a/widget/gtk/nsGtkKeyUtils.cpp b/widget/gtk/nsGtkKeyUtils.cpp
index 2deda1e4d1ff..c5bb5007a75e 100644
--- a/widget/gtk/nsGtkKeyUtils.cpp
+++ b/widget/gtk/nsGtkKeyUtils.cpp
@@ -651,7 +651,7 @@ KeymapWrapper::InitInputEvent(WidgetInputEvent& aInputEvent,
         case eMouseScrollEventClass:
         case eWheelEventClass:
         case eDragEventClass:
-        case NS_SIMPLE_GESTURE_EVENT:
+        case eSimpleGestureEventClass:
             break;
         default:
             return;
diff --git a/widget/windows/KeyboardLayout.cpp b/widget/windows/KeyboardLayout.cpp
index 025ed179dda0..e248235b9c7c 100644
--- a/widget/windows/KeyboardLayout.cpp
+++ b/widget/windows/KeyboardLayout.cpp
@@ -285,7 +285,7 @@ ModifierKeyState::InitInputEvent(WidgetInputEvent& aInputEvent) const
     case eMouseScrollEventClass:
     case eWheelEventClass:
     case eDragEventClass:
-    case NS_SIMPLE_GESTURE_EVENT:
+    case eSimpleGestureEventClass:
       InitMouseEvent(aInputEvent);
       break;
     default:
@@ -299,7 +299,7 @@ ModifierKeyState::InitMouseEvent(WidgetInputEvent& aMouseEvent) const
   NS_ASSERTION(aMouseEvent.mClass == eMouseEventClass ||
                aMouseEvent.mClass == eWheelEventClass ||
                aMouseEvent.mClass == eDragEventClass ||
-               aMouseEvent.mClass == NS_SIMPLE_GESTURE_EVENT,
+               aMouseEvent.mClass == eSimpleGestureEventClass,
                "called with non-mouse event");
 
   if (XRE_GetWindowsEnvironment() == WindowsEnvironmentType_Metro) {