diff -r 000000000000 -r 6474c204b198 widget/xpwidgets/nsPrimitiveHelpers.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/widget/xpwidgets/nsPrimitiveHelpers.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,65 @@
+/* -*- 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 nsPrimitiveHelpers_h___
+#define nsPrimitiveHelpers_h___
+
+#include "nsError.h"
+#include "nscore.h"
+
+class nsISupports;
+
+
+class nsPrimitiveHelpers
+{
+public:
+
+    // Given some data and the flavor it corresponds to, creates the appropriate
+    // nsISupports* wrapper for passing across IDL boundaries. The length parameter
+    // should not include the null if the data is null terminated.
+  static void CreatePrimitiveForData ( const char* aFlavor, const void* aDataBuff,
+                                         uint32_t aDataLen, nsISupports** aPrimitive ) ;
+
+    // Given a nsISupports* primitive and the flavor it represents, creates a new data
+    // buffer with the data in it. This data will be null terminated, but the length
+    // parameter does not reflect that.
+  static void CreateDataFromPrimitive ( const char* aFlavor, nsISupports* aPrimitive, 
+                                         void** aDataBuff, uint32_t aDataLen ) ;
+
+    // Given a unicode buffer (flavor text/unicode), this converts it to plain text using
+    // the appropriate platform charset encoding. |inUnicodeLen| is the length of the input
+    // string, not the # of bytes in the buffer. |outPlainTextData| is null terminated, 
+    // but its length parameter, |outPlainTextLen|, does not reflect that.
+  static nsresult ConvertUnicodeToPlatformPlainText ( char16_t* inUnicode, int32_t inUnicodeLen, 
+                                                    char** outPlainTextData, int32_t* outPlainTextLen ) ;
+
+    // Given a char buffer (flavor text/plaikn), this converts it to unicode using
+    // the appropriate platform charset encoding. |outUnicode| is null terminated, 
+    // but its length parameter, |outUnicodeLen|, does not reflect that. |outUnicodeLen| is
+    // the length of the string in characters, not bytes.
+  static nsresult ConvertPlatformPlainTextToUnicode ( const char* inText, int32_t inTextLen, 
+                                                    char16_t** outUnicode, int32_t* outUnicodeLen ) ;
+
+}; // class nsPrimitiveHelpers
+
+
+
+class nsLinebreakHelpers
+{
+public:
+
+    // Given some data, convert from the platform linebreaks into the LF expected by the
+    // DOM. This will attempt to convert the data in place, but the buffer may still need to
+    // be reallocated regardless (disposing the old buffer is taken care of internally, see
+    // the note below).
+    //
+    // NOTE: this assumes that it can use nsMemory to dispose of the old buffer.
+  static nsresult ConvertPlatformToDOMLinebreaks ( const char* inFlavor, void** ioData, int32_t* ioLengthInBytes ) ;
+
+}; // class nsLinebreakHelpers
+
+
+#endif // nsPrimitiveHelpers_h___