diff --git a/widget/BasicEvents.h b/widget/BasicEvents.h
index 902299bb8722..97ea284e1578 100644
--- a/widget/BasicEvents.h
+++ b/widget/BasicEvents.h
@@ -495,6 +495,61 @@ public:
   bool IsAllowedToDispatchDOMEvent() const;
 };
 
+/******************************************************************************
+ * mozilla::NativeEventData
+ *
+ * WidgetGUIEvent's mPluginEvent member used to be a void* pointer,
+ * used to reference external, OS-specific data structures.
+ *
+ * That void* pointer wasn't serializable by itself, causing
+ * certain plugin events not to function in e10s. See bug 586656.
+ *
+ * To make this serializable, we changed this void* pointer into
+ * a proper buffer, and copy these external data structures into this
+ * buffer.
+ *
+ * That buffer is NativeEventData::mBuffer below.
+ *
+ * We wrap this in that NativeEventData class providing operators to
+ * be compatible with existing code that was written around
+ * the old void* field.
+ ******************************************************************************/
+
+class NativeEventData final
+{
+  nsTArray<uint8_t> mBuffer;
+
+  friend struct IPC::ParamTraits<mozilla::NativeEventData>;
+
+public:
+
+  MOZ_EXPLICIT_CONVERSION operator bool() const
+  {
+    return !mBuffer.IsEmpty();
+  }
+
+  template<typename T>
+  MOZ_EXPLICIT_CONVERSION operator const T*() const
+  {
+    return mBuffer.IsEmpty()
+           ? nullptr
+           : reinterpret_cast<const T*>(mBuffer.Elements());
+  }
+
+  template <typename T>
+  void Copy(const T& other)
+  {
+    static_assert(!mozilla::IsPointer<T>::value, "Don't want a pointer!");
+    mBuffer.SetLength(sizeof(T));
+    memcpy(mBuffer.Elements(), &other, mBuffer.Length());
+  }
+
+  void Clear()
+  {
+    mBuffer.Clear();
+  }
+};
+
 /******************************************************************************
  * mozilla::WidgetGUIEvent
  ******************************************************************************/
@@ -537,24 +592,6 @@ public:
   nsCOMPtr<nsIWidget> mWidget;
 
   /*
-   * Explanation for this PluginEvent class:
-   *
-   * WidgetGUIEvent's mPluginEvent member used to be a void* pointer,
-   * used to reference external, OS-specific data structures.
-   *
-   * That void* pointer wasn't serializable by itself, causing
-   * certain plugin events not to function in e10s. See bug 586656.
-   *
-   * To make this serializable, we changed this void* pointer into
-   * a proper buffer, and copy these external data structures into this
-   * buffer.
-   *
-   * That buffer is PluginEvent::mBuffer below.
-   *
-   * We wrap this in that PluginEvent class providing operators to
-   * be compatible with existing code that was written around
-   * the old void* field.
-   *
    * Ideally though, we wouldn't allow arbitrary reinterpret_cast'ing here;
    * instead, we would at least store type information here so that
    * this class can't be used to reinterpret one structure type into another.
@@ -562,40 +599,7 @@ public:
    * WidgetGUIEvent and other Event classes to remove the need for this
    * mPluginEvent field.
    */
-  class PluginEvent final
-  {
-    nsTArray<uint8_t> mBuffer;
-
-    friend struct IPC::ParamTraits<mozilla::WidgetGUIEvent>;
-
-  public:
-
-    MOZ_EXPLICIT_CONVERSION operator bool() const
-    {
-      return !mBuffer.IsEmpty();
-    }
-
-    template<typename T>
-    MOZ_EXPLICIT_CONVERSION operator const T*() const
-    {
-      return mBuffer.IsEmpty()
-             ? nullptr
-             : reinterpret_cast<const T*>(mBuffer.Elements());
-    }
-
-    template <typename T>
-    void Copy(const T& other)
-    {
-      static_assert(!mozilla::IsPointer<T>::value, "Don't want a pointer!");
-      mBuffer.SetLength(sizeof(T));
-      memcpy(mBuffer.Elements(), &other, mBuffer.Length());
-    }
-
-    void Clear()
-    {
-      mBuffer.Clear();
-    }
-  };
+  typedef NativeEventData PluginEvent;
 
   // Event for NPAPI plugin
   PluginEvent mPluginEvent;
diff --git a/widget/EventForwards.h b/widget/EventForwards.h
index 64fc4a29a8b5..3d5ae180de47 100644
--- a/widget/EventForwards.h
+++ b/widget/EventForwards.h
@@ -139,6 +139,8 @@ struct EventFlags;
 
 class WidgetEventTime;
 
+class NativeEventData;
+
 // TextEvents.h
 struct AlternativeCharCode;
 struct ShortcutKeyCandidate;
diff --git a/widget/nsGUIEventIPC.h b/widget/nsGUIEventIPC.h
index f7cfef085406..e4ae78fa4624 100644
--- a/widget/nsGUIEventIPC.h
+++ b/widget/nsGUIEventIPC.h
@@ -88,6 +88,22 @@ struct ParamTraits<mozilla::WidgetEvent>
   }
 };
 
+template<>
+struct ParamTraits<mozilla::NativeEventData>
+{
+  typedef mozilla::NativeEventData paramType;
+
+  static void Write(Message* aMsg, const paramType& aParam)
+  {
+    WriteParam(aMsg, aParam.mBuffer);
+  }
+
+  static bool Read(const Message* aMsg, void** aIter, paramType* aResult)
+  {
+    return ReadParam(aMsg, aIter, &aResult->mBuffer);
+  }
+};
+
 template<>
 struct ParamTraits<mozilla::WidgetGUIEvent>
 {
@@ -96,13 +112,13 @@ struct ParamTraits<mozilla::WidgetGUIEvent>
   static void Write(Message* aMsg, const paramType& aParam)
   {
     WriteParam(aMsg, static_cast<mozilla::WidgetEvent>(aParam));
-    WriteParam(aMsg, aParam.mPluginEvent.mBuffer);
+    WriteParam(aMsg, aParam.mPluginEvent);
   }
 
   static bool Read(const Message* aMsg, void** aIter, paramType* aResult)
   {
     return ReadParam(aMsg, aIter, static_cast<mozilla::WidgetEvent*>(aResult)) &&
-           ReadParam(aMsg, aIter, &aResult->mPluginEvent.mBuffer);
+           ReadParam(aMsg, aIter, &aResult->mPluginEvent);
   }
 };