diff -r 000000000000 -r 6474c204b198 dom/ipc/nsICachedFileDescriptorListener.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/ipc/nsICachedFileDescriptorListener.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,38 @@
+/* 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 mozilla_dom_ipc_nsICachedFileDescriptorListener_h
+#define mozilla_dom_ipc_nsICachedFileDescriptorListener_h
+
+#include "nsISupports.h"
+
+#ifndef NS_NO_VTABLE
+#define NS_NO_VTABLE
+#endif
+
+#define NS_ICACHEDFILEDESCRIPTORLISTENER_IID \
+  {0x2cedaee0, 0x6ef2, 0x4f60, {0x9a, 0x6c, 0xdf, 0x4e, 0x4d, 0x65, 0x6a, 0xf7}}
+
+class nsAString;
+
+namespace mozilla {
+namespace ipc {
+class FileDescriptor;
+}
+}
+
+class NS_NO_VTABLE nsICachedFileDescriptorListener : public nsISupports
+{
+public:
+  NS_DECLARE_STATIC_IID_ACCESSOR(NS_ICACHEDFILEDESCRIPTORLISTENER_IID)
+
+  virtual void
+  OnCachedFileDescriptor(const nsAString& aPath,
+                         const mozilla::ipc::FileDescriptor& aFD) = 0;
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(nsICachedFileDescriptorListener,
+                              NS_ICACHEDFILEDESCRIPTORLISTENER_IID)
+
+#endif // mozilla_dom_ipc_nsICachedFileDescriptorListener_h