diff --git a/dom/indexedDB/IDBEvents.cpp b/dom/indexedDB/IDBEvents.cpp
index 4cd19aebc725..8a321072b7ea 100644
--- a/dom/indexedDB/IDBEvents.cpp
+++ b/dom/indexedDB/IDBEvents.cpp
@@ -57,7 +57,7 @@ mozilla::dom::indexedDB::CreateGenericEvent(mozilla::dom::EventTarget* aOwner,
 }
 
 // static
-already_AddRefed<nsDOMEvent>
+already_AddRefed<IDBVersionChangeEvent>
 IDBVersionChangeEvent::CreateInternal(mozilla::dom::EventTarget* aOwner,
                                       const nsAString& aType,
                                       uint64_t aOldVersion,
diff --git a/dom/indexedDB/IDBEvents.h b/dom/indexedDB/IDBEvents.h
index d2194b2405df..fe838c9a7954 100644
--- a/dom/indexedDB/IDBEvents.h
+++ b/dom/indexedDB/IDBEvents.h
@@ -57,6 +57,20 @@ public:
     return mozilla::dom::IDBVersionChangeEventBinding::Wrap(aCx, aScope, this);
   }
 
+  static already_AddRefed<IDBVersionChangeEvent>
+  Constructor(const GlobalObject& aGlobal,
+              const NonNull<nsAString>& aType,
+              const IDBVersionChangeEventInit& aOptions,
+              ErrorResult& aRv)
+  {
+    uint64_t newVersion = 0;
+    if (!aOptions.mNewVersion.IsNull()) {
+      newVersion = aOptions.mNewVersion.Value();
+    }
+    nsCOMPtr<EventTarget> target = do_QueryInterface(aGlobal.Get());
+    return CreateInternal(target, aType, aOptions.mOldVersion, newVersion);
+  }
+
   uint64_t OldVersion()
   {
     return mOldVersion;
@@ -126,7 +140,7 @@ protected:
   }
   virtual ~IDBVersionChangeEvent() { }
 
-  static already_AddRefed<nsDOMEvent>
+  static already_AddRefed<IDBVersionChangeEvent>
   CreateInternal(mozilla::dom::EventTarget* aOwner,
                  const nsAString& aType,
                  uint64_t aOldVersion,
diff --git a/dom/indexedDB/test/unit/test_setVersion_events.js b/dom/indexedDB/test/unit/test_setVersion_events.js
index 26a531f32252..29a2089c0c63 100644
--- a/dom/indexedDB/test/unit/test_setVersion_events.js
+++ b/dom/indexedDB/test/unit/test_setVersion_events.js
@@ -157,6 +157,21 @@ function testSteps()
 
   is(versionChangeEventCount, 3, "Saw all expected events");
 
+  event = new IDBVersionChangeEvent("versionchange");
+  ok(event, "Should be able to create an event with just passing in the type");
+  event = new IDBVersionChangeEvent("versionchange", {oldVersion: 1});
+  ok(event, "Should be able to create an event with just the old version");
+  is(event.oldVersion, 1, "Correct old version");
+  is(event.newVersion, null, "Correct new version");
+  event = new IDBVersionChangeEvent("versionchange", {newVersion: 1});
+  ok(event, "Should be able to create an event with just the new version");
+  is(event.oldVersion, 0, "Correct old version");
+  is(event.newVersion, 1, "Correct new version");
+  event = new IDBVersionChangeEvent("versionchange", {oldVersion: 1, newVersion: 2});
+  ok(event, "Should be able to create an event with both versions");
+  is(event.oldVersion, 1, "Correct old version");
+  is(event.newVersion, 2, "Correct new version");
+
   finishTest();
   yield;
 }
diff --git a/dom/webidl/IDBVersionChangeEvent.webidl b/dom/webidl/IDBVersionChangeEvent.webidl
index ea0e88be3d32..65612911b189 100644
--- a/dom/webidl/IDBVersionChangeEvent.webidl
+++ b/dom/webidl/IDBVersionChangeEvent.webidl
@@ -3,14 +3,21 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/.
  *
- * IDBVersionChangeEvent is defined in:
- * https://dvcs.w3.org/hg/IndexedDB/raw-file/tip/Overview.html
+ * The origin of this IDL file is
+ * https://dvcs.w3.org/hg/IndexedDB/raw-file/tip/Overview.html#idl-def-IDBVersionChangeEvent
  *
  * Copyright © 2012 W3C® (MIT, ERCIM, Keio), All Rights Reserved. W3C
  * liability, trademark and document use rules apply.
  */
 
-interface IDBVersionChangeEvent : Event {
-  readonly attribute unsigned long long  oldVersion;
-  readonly attribute unsigned long long? newVersion;
+dictionary IDBVersionChangeEventInit : EventInit {
+    unsigned long long  oldVersion = 0;
+    unsigned long long? newVersion = null;
 };
+
+[Constructor(DOMString type, optional IDBVersionChangeEventInit eventInitDict)]
+interface IDBVersionChangeEvent : Event {
+    readonly    attribute unsigned long long  oldVersion;
+    readonly    attribute unsigned long long? newVersion;
+};
+