diff --git a/content/base/public/nsIDocument.h b/content/base/public/nsIDocument.h
index 86f8aa0ef7c6..c73e8f52c75f 100644
--- a/content/base/public/nsIDocument.h
+++ b/content/base/public/nsIDocument.h
@@ -101,8 +101,8 @@ class nsFrameLoader;
 
 // IID for the nsIDocument interface
 #define NS_IDOCUMENT_IID      \
-{ 0x6e467d95, 0x9934, 0x422a, \
- { 0x81, 0x07, 0x3f, 0xff, 0xe1, 0x38, 0xe6, 0x1e } }
+{ 0xdd9bd470, 0x6315, 0x4e67, \
+  { 0xa8, 0x8a, 0x78, 0xbf, 0x92, 0xb4, 0x5a, 0xdf } }
 
 // Flag for AddStyleSheet().
 #define NS_STYLESHEET_FROM_CATALOG                (1 << 0)
@@ -125,7 +125,8 @@ public:
       mCompatMode(eCompatibility_FullStandards),
       mIsInitialDocumentInWindow(PR_FALSE),
       mMayStartLayout(PR_TRUE),
-      mPartID(0)
+      mPartID(0),
+      mJSObject(nsnull)
   {
     mParentPtrBits |= PARENT_BIT_INDOCUMENT;
   }
@@ -994,6 +995,16 @@ public:
     mMayStartLayout = aMayStartLayout;
   }
 
+  JSObject* GetJSObject() const
+  {
+    return mJSObject;
+  }
+
+  void SetJSObject(JSObject *aJSObject)
+  {
+    mJSObject = aJSObject;
+  }
+
   // This method should return an addrefed nsIParser* or nsnull. Implementations
   // should transfer ownership of the parser to the caller.
   virtual already_AddRefed<nsIParser> GetFragmentParser() {
@@ -1236,6 +1247,12 @@ protected:
   nsCOMPtr<nsIDocument> mDisplayDocument;
 
   PRUint32 mEventsSuppressed;
+
+private:
+  // JSObject cache. Only to be used for performance
+  // optimizations. This will be set once this document is touched
+  // from JS, and it will be unset once the JSObject is finalized.
+  JSObject *mJSObject;
 };
 
 NS_DEFINE_STATIC_IID_ACCESSOR(nsIDocument, NS_IDOCUMENT_IID)
diff --git a/dom/base/nsDOMClassInfo.cpp b/dom/base/nsDOMClassInfo.cpp
index cbd3489d40af..dbe9bb9ba069 100644
--- a/dom/base/nsDOMClassInfo.cpp
+++ b/dom/base/nsDOMClassInfo.cpp
@@ -6986,13 +6986,8 @@ nsNodeSH::PreCreate(nsISupports *nativeObj, JSContext *cx, JSObject *globalObj,
   // to wrap here? But that's not always reachable, let's use
   // globalObj for now...
 
-  nsIXPConnectJSObjectHolder *wrapper;
-  if (native_parent == doc &&
-      (wrapper = static_cast<nsIXPConnectJSObjectHolder*>(doc->GetWrapper()))) {
-    wrapper->GetJSObject(parentObj);
-    if(*parentObj) {
-      return NS_OK;
-    }
+  if (native_parent == doc && (*parentObj = doc->GetJSObject())) {
+    return NS_OK;
   }
 
   jsval v;
@@ -8256,6 +8251,10 @@ nsDocumentSH::PostCreate(nsIXPConnectWrappedNative *wrapper, JSContext *cx,
     return NS_ERROR_UNEXPECTED;
   }
 
+  // Cache the document's JSObject on the document so we can optimize
+  // nsNodeSH::PreCreate() to avoid nested WrapNative() calls.
+  doc->SetJSObject(obj);
+
   nsresult rv = nsNodeSH::PostCreate(wrapper, cx, obj);
   NS_ENSURE_SUCCESS(rv, rv);
 
@@ -8289,6 +8288,20 @@ nsDocumentSH::PostCreate(nsIXPConnectWrappedNative *wrapper, JSContext *cx,
   return NS_OK;
 }
 
+NS_IMETHODIMP
+nsDocumentSH::Finalize(nsIXPConnectWrappedNative *wrapper, JSContext *cx,
+                       JSObject *obj)
+{
+  nsCOMPtr<nsIDocument> doc = do_QueryWrappedNative(wrapper);
+  if (!doc) {
+    return NS_ERROR_UNEXPECTED;
+  }
+
+  doc->SetJSObject(nsnull);
+
+  return nsNodeSH::Finalize(wrapper, cx, obj);
+}
+
 // HTMLDocument helper
 
 // static
diff --git a/dom/base/nsDOMClassInfo.h b/dom/base/nsDOMClassInfo.h
index 5205ee53cdb3..a47d64b71a83 100644
--- a/dom/base/nsDOMClassInfo.h
+++ b/dom/base/nsDOMClassInfo.h
@@ -864,6 +864,8 @@ public:
   NS_IMETHOD GetFlags(PRUint32* aFlags);
   NS_IMETHOD PostCreate(nsIXPConnectWrappedNative *wrapper, JSContext *cx,
                         JSObject *obj);
+  NS_IMETHOD Finalize(nsIXPConnectWrappedNative *wrapper, JSContext *cx,
+                      JSObject *obj);
 
   static nsIClassInfo *doCreate(nsDOMClassInfoData* aData)
   {
diff --git a/dom/base/nsWrapperCache.h b/dom/base/nsWrapperCache.h
index 993471d93b14..2d606c6aae28 100644
--- a/dom/base/nsWrapperCache.h
+++ b/dom/base/nsWrapperCache.h
@@ -73,7 +73,7 @@ public:
    * including nsIXPConnect, because we don't want to make everyone require
    * JS and XPConnect.
    */
-  nsISupports* GetWrapper() const
+  nsISupports* GetWrapper()
   {
     return reinterpret_cast<nsISupports*>(mWrapperPtrBits & ~kWrapperBitMask);
   }