diff -r 000000000000 -r 6474c204b198 xpcom/components/nsIClassInfo.idl
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xpcom/components/nsIClassInfo.idl	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,99 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * 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/. */
+
+#include "nsISupports.idl"
+
+/**
+ * Provides information about a specific implementation class.  If you want
+ * your class to implement nsIClassInfo, see nsIClassInfoImpl.h for
+ * instructions--you most likely do not want to inherit from nsIClassInfo.
+ */
+
+[scriptable, uuid(986c11d0-f340-11d4-9075-0010a4e73d9a)]
+interface nsIClassInfo : nsISupports
+{
+    /**
+     * Get an ordered list of the interface ids that instances of the class 
+     * promise to implement. Note that nsISupports is an implicit member 
+     * of any such list and need not be included. 
+     *
+     * Should set *count = 0 and *array = null and return NS_OK if getting the 
+     * list is not supported.
+     */
+    void getInterfaces(out uint32_t count, 
+                       [array, size_is(count), retval] out nsIIDPtr array);
+
+    /**
+     * Get a language mapping specific helper object that may assist in using
+     * objects of this class in a specific lanaguage. For instance, if asked
+     * for the helper for nsIProgrammingLanguage::JAVASCRIPT this might return 
+     * an object that can be QI'd into the nsIXPCScriptable interface to assist 
+     * XPConnect in supplying JavaScript specific behavior to callers of the 
+     * instance object.
+     *
+     * see: nsIProgrammingLanguage.idl
+     *
+     * Should return null if no helper available for given language.
+     */
+    nsISupports getHelperForLanguage(in uint32_t language);
+
+    /**
+     * A contract ID through which an instance of this class can be created
+     * (or accessed as a service, if |flags & SINGLETON|), or null.
+     */
+    readonly attribute string   contractID;
+
+    /**
+     * A human readable string naming the class, or null.
+     */
+    readonly attribute string   classDescription;
+
+    /**
+     * A class ID through which an instance of this class can be created
+     * (or accessed as a service, if |flags & SINGLETON|), or null.
+     */
+    readonly attribute nsCIDPtr classID;
+
+    /**
+     * Return language type from list in nsIProgrammingLanguage
+     */
+
+    readonly attribute uint32_t implementationLanguage;
+
+    /**
+     * Bitflags for 'flags' attribute.
+     */
+    const uint32_t SINGLETON            = 1 << 0;
+    const uint32_t THREADSAFE           = 1 << 1;
+    const uint32_t MAIN_THREAD_ONLY     = 1 << 2;
+    const uint32_t DOM_OBJECT           = 1 << 3;
+    const uint32_t PLUGIN_OBJECT        = 1 << 4;
+    const uint32_t SINGLETON_CLASSINFO  = 1 << 5;
+
+    /**
+     * 'flags' attribute bitflag: whether objects of this type implement
+     * nsIContent.
+     */
+    const uint32_t CONTENT_NODE         = 1 << 6;
+    
+    // The high order bit is RESERVED for consumers of these flags. 
+    // No implementor of this interface should ever return flags 
+    // with this bit set.
+    const uint32_t RESERVED             = 1 << 31;
+
+
+    readonly attribute uint32_t flags;
+
+    /**
+     * Also a class ID through which an instance of this class can be created
+     * (or accessed as a service, if |flags & SINGLETON|).  If the class does
+     * not have a CID, it should return NS_ERROR_NOT_AVAILABLE.  This attribute
+     * exists so C++ callers can avoid allocating and freeing a CID, as would
+     * happen if they used classID.
+     */
+    [noscript] readonly attribute nsCID classIDNoAlloc;
+
+};