--- a/dom/base/nsDOMWindowUtils.cpp
+++ b/dom/base/nsDOMWindowUtils.cpp
@@ -759,17 +759,17 @@ nsDOMWindowUtils::SendPointerEventCommon
 
   WidgetPointerEvent event(true, msg, widget);
   event.mModifiers = nsContentUtils::GetWidgetModifiers(aModifiers);
   event.button = aButton;
   event.buttons = nsContentUtils::GetButtonsFlagForButton(aButton);
   event.pressure = aPressure;
   event.inputSource = aInputSourceArg;
   event.pointerId = aPointerId;
-  event.width = aWidth;
+  event.mWidth = aWidth;
   event.height = aHeight;
   event.tiltX = aTiltX;
   event.tiltY = aTiltY;
   event.isPrimary = (nsIDOMMouseEvent::MOZ_SOURCE_MOUSE == aInputSourceArg) ? true : aIsPrimary;
   event.mClickCount = aClickCount;
   event.mTime = PR_IntervalNow();
   event.mFlags.mIsSynthesizedForTests = aOptionalArgCount >= 10 ? aIsSynthesized : true;
 

--- a/dom/events/EventStateManager.cpp
+++ b/dom/events/EventStateManager.cpp
@@ -3831,17 +3831,17 @@ CreateMouseOrPointerWidgetEvent(WidgetMo
       js::ProfileEntry::Category::EVENTS);
 
     nsAutoPtr<WidgetPointerEvent> newPointerEvent;
     newPointerEvent =
       new WidgetPointerEvent(aMouseEvent->IsTrusted(), aMessage,
                              aMouseEvent->mWidget);
     newPointerEvent->isPrimary = sourcePointer->isPrimary;
     newPointerEvent->pointerId = sourcePointer->pointerId;
-    newPointerEvent->width = sourcePointer->width;
+    newPointerEvent->mWidth = sourcePointer->mWidth;
     newPointerEvent->height = sourcePointer->height;
     newPointerEvent->inputSource = sourcePointer->inputSource;
     newPointerEvent->relatedTarget =
       nsIPresShell::GetPointerCapturingContent(sourcePointer->pointerId)
         ? nullptr
         : aRelatedContent;
     aNewEvent = newPointerEvent.forget();
   } else {

--- a/dom/events/PointerEvent.cpp
+++ b/dom/events/PointerEvent.cpp
@@ -82,17 +82,17 @@ PointerEvent::Constructor(EventTarget* a
                     aParam.mView, aParam.mDetail, aParam.mScreenX,
                     aParam.mScreenY, aParam.mClientX, aParam.mClientY,
                     false, false, false, false, aParam.mButton,
                     aParam.mRelatedTarget);
   e->InitializeExtraMouseEventDictionaryMembers(aParam);
 
   WidgetPointerEvent* widgetEvent = e->mEvent->AsPointerEvent();
   widgetEvent->pointerId = aParam.mPointerId;
-  widgetEvent->width = aParam.mWidth;
+  widgetEvent->mWidth = aParam.mWidth;
   widgetEvent->height = aParam.mHeight;
   widgetEvent->pressure = aParam.mPressure;
   widgetEvent->tiltX = aParam.mTiltX;
   widgetEvent->tiltY = aParam.mTiltY;
   widgetEvent->inputSource = ConvertStringToPointerType(aParam.mPointerType);
   widgetEvent->isPrimary = aParam.mIsPrimary;
   widgetEvent->buttons = aParam.mButtons;
 
@@ -121,17 +121,17 @@ int32_t
 PointerEvent::PointerId()
 {
   return mEvent->AsPointerEvent()->pointerId;
 }
 
 int32_t
 PointerEvent::Width()
 {
-  return mEvent->AsPointerEvent()->width;
+  return mEvent->AsPointerEvent()->mWidth;
 }
 
 int32_t
 PointerEvent::Height()
 {
   return mEvent->AsPointerEvent()->height;
 }
 

--- a/layout/base/nsPresShell.cpp
+++ b/layout/base/nsPresShell.cpp
@@ -7195,17 +7195,17 @@ DispatchPointerFromMouseOrTouch(PresShel
       }
 
       WidgetPointerEvent event(touchEvent->IsTrusted(), pointerMessage,
                                touchEvent->mWidget);
       event.isPrimary = i == 0;
       event.pointerId = touch->Identifier();
       event.mRefPoint = touch->mRefPoint;
       event.mModifiers = touchEvent->mModifiers;
-      event.width = touch->RadiusX();
+      event.mWidth = touch->RadiusX();
       event.height = touch->RadiusY();
       event.tiltX = touch->tiltX;
       event.tiltY = touch->tiltY;
       event.mTime = touchEvent->mTime;
       event.mTimeStamp = touchEvent->mTimeStamp;
       event.mFlags = touchEvent->mFlags;
       event.button = WidgetMouseEvent::eLeftButton;
       event.buttons = WidgetMouseEvent::eLeftButtonFlag;

--- a/widget/MouseEvents.h
+++ b/widget/MouseEvents.h
@@ -661,36 +661,36 @@ private:
  ******************************************************************************/
 
 class WidgetPointerEvent : public WidgetMouseEvent
 {
   friend class mozilla::dom::PBrowserParent;
   friend class mozilla::dom::PBrowserChild;
 
   WidgetPointerEvent()
-    : width(0)
+    : mWidth(0)
     , height(0)
     , isPrimary(true)
   {
   }
 
 public:
   virtual WidgetPointerEvent* AsPointerEvent() override { return this; }
 
   WidgetPointerEvent(bool aIsTrusted, EventMessage aMsg, nsIWidget* w)
     : WidgetMouseEvent(aIsTrusted, aMsg, w, ePointerEventClass, eReal)
-    , width(0)
+    , mWidth(0)
     , height(0)
     , isPrimary(true)
   {
   }
 
   explicit WidgetPointerEvent(const WidgetMouseEvent& aEvent)
     : WidgetMouseEvent(aEvent)
-    , width(0)
+    , mWidth(0)
     , height(0)
     , isPrimary(true)
   {
     mClass = ePointerEventClass;
   }
 
   virtual WidgetEvent* Duplicate() const override
   {
@@ -699,27 +699,27 @@ public:
     // Not copying widget, it is a weak reference.
     WidgetPointerEvent* result =
       new WidgetPointerEvent(false, mMessage, nullptr);
     result->AssignPointerEventData(*this, true);
     result->mFlags = mFlags;
     return result;
   }
 
-  uint32_t width;
+  uint32_t mWidth;
   uint32_t height;
   bool isPrimary;
 
   // XXX Not tested by test_assign_event_data.html
   void AssignPointerEventData(const WidgetPointerEvent& aEvent,
                               bool aCopyTargets)
   {
     AssignMouseEventData(aEvent, aCopyTargets);
 
-    width = aEvent.width;
+    mWidth = aEvent.mWidth;
     height = aEvent.height;
     isPrimary = aEvent.isPrimary;
   }
 };
 
 } // namespace mozilla
 
 #endif // mozilla_MouseEvents_h__

--- a/widget/nsGUIEventIPC.h
+++ b/widget/nsGUIEventIPC.h
@@ -282,29 +282,29 @@ template<>
 struct ParamTraits<mozilla::WidgetPointerEvent>
 {
   typedef mozilla::WidgetPointerEvent paramType;
 
   static void Write(Message* aMsg, const paramType& aParam)
   {
     WriteParam(aMsg, static_cast<mozilla::WidgetMouseEvent>(aParam));
     WriteParam(aMsg, aParam.pointerId);
-    WriteParam(aMsg, aParam.width);
+    WriteParam(aMsg, aParam.mWidth);
     WriteParam(aMsg, aParam.height);
     WriteParam(aMsg, aParam.tiltX);
     WriteParam(aMsg, aParam.tiltY);
     WriteParam(aMsg, aParam.isPrimary);
   }
 
   static bool Read(const Message* aMsg, PickleIterator* aIter, paramType* aResult)
   {
     bool rv =
       ReadParam(aMsg, aIter, static_cast<mozilla::WidgetMouseEvent*>(aResult)) &&
       ReadParam(aMsg, aIter, &aResult->pointerId) &&
-      ReadParam(aMsg, aIter, &aResult->width) &&
+      ReadParam(aMsg, aIter, &aResult->mWidth) &&
       ReadParam(aMsg, aIter, &aResult->height) &&
       ReadParam(aMsg, aIter, &aResult->tiltX) &&
       ReadParam(aMsg, aIter, &aResult->tiltY) &&
       ReadParam(aMsg, aIter, &aResult->isPrimary);
     return rv;
   }
 };