diff -r 000000000000 -r 6474c204b198 widget/xpwidgets/nsTransferable.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/xpwidgets/nsTransferable.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,82 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * 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/. */
+
+#ifndef nsTransferable_h__
+#define nsTransferable_h__
+
+#include "nsIFormatConverter.h"
+#include "nsITransferable.h"
+#include "nsCOMPtr.h"
+#include "nsString.h"
+#include "nsTArray.h"
+
+class nsString;
+class nsDataObj;
+
+//
+// DataStruct
+//
+// Holds a flavor (a mime type) that describes the data and the associated data.
+//
+struct DataStruct
+{
+  DataStruct ( const char* aFlavor )
+    : mDataLen(0), mFlavor(aFlavor), mCacheFileName(nullptr) { }
+  ~DataStruct();
+  
+  const nsCString& GetFlavor() const { return mFlavor; }
+  void SetData( nsISupports* inData, uint32_t inDataLen );
+  void GetData( nsISupports** outData, uint32_t *outDataLen );
+  already_AddRefed<nsIFile> GetFileSpec(const char* aFileName);
+  bool IsDataAvailable() const { return (mData && mDataLen > 0) || (!mData && mCacheFileName); }
+  
+protected:
+
+  enum {
+    // The size of data over which we write the data to disk rather than
+    // keep it around in memory.
+    kLargeDatasetSize = 1000000        // 1 million bytes
+  };
+  
+  nsresult WriteCache(nsISupports* aData, uint32_t aDataLen );
+  nsresult ReadCache(nsISupports** aData, uint32_t* aDataLen );
+  
+  nsCOMPtr<nsISupports> mData;   // OWNER - some varient of primitive wrapper
+  uint32_t mDataLen;
+  const nsCString mFlavor;
+  char *   mCacheFileName;
+
+};
+
+/**
+ * XP Transferable wrapper
+ */
+
+class nsTransferable : public nsITransferable
+{
+public:
+
+  nsTransferable();
+  virtual ~nsTransferable();
+
+    // nsISupports
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSITRANSFERABLE
+
+protected:
+
+    // get flavors w/out converter
+  nsresult GetTransferDataFlavors(nsISupportsArray** aDataFlavorList);
+ 
+  nsTArray<DataStruct> mDataArray;
+  nsCOMPtr<nsIFormatConverter> mFormatConv;
+  bool mPrivateData;
+#if DEBUG
+  bool mInitialized;
+#endif
+
+};
+
+#endif // nsTransferable_h__