diff -r 000000000000 -r 6474c204b198 caps/src/nsJSPrincipals.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/caps/src/nsJSPrincipals.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,73 @@
+/* -*- Mode: C++; tab-width: 4; 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 "xpcprivate.h"
+#include "nsString.h"
+#include "nsIObjectOutputStream.h"
+#include "nsIObjectInputStream.h"
+#include "nsJSPrincipals.h"
+#include "plstr.h"
+#include "nsXPIDLString.h"
+#include "nsCOMPtr.h"
+#include "nsIJSRuntimeService.h"
+#include "nsIServiceManager.h"
+#include "nsMemory.h"
+#include "nsStringBuffer.h"
+
+// for mozilla::dom::workers::kJSPrincipalsDebugToken
+#include "mozilla/dom/workers/Workers.h"
+
+/* static */ bool
+nsJSPrincipals::Subsume(JSPrincipals *jsprin, JSPrincipals *other)
+{
+    bool result;
+    nsresult rv = nsJSPrincipals::get(jsprin)->Subsumes(nsJSPrincipals::get(other), &result);
+    return NS_SUCCEEDED(rv) && result;
+}
+
+/* static */ void
+nsJSPrincipals::Destroy(JSPrincipals *jsprin)
+{
+    // The JS runtime can call this method during the last GC when
+    // nsScriptSecurityManager is destroyed. So we must not assume here that
+    // the security manager still exists.
+
+    nsJSPrincipals *nsjsprin = nsJSPrincipals::get(jsprin);
+
+    // We need to destroy the nsIPrincipal. We'll do this by adding
+    // to the refcount and calling release
+
+#ifdef NS_BUILD_REFCNT_LOGGING
+    // The refcount logging considers AddRef-to-1 to indicate creation,
+    // so trick it into thinking it's otherwise, but balance the
+    // Release() we do below.
+    nsjsprin->refcount++;
+    nsjsprin->AddRef();
+    nsjsprin->refcount--;
+#else
+    nsjsprin->refcount++;
+#endif
+    nsjsprin->Release();
+}
+
+#ifdef DEBUG
+
+// Defined here so one can do principals->dump() in the debugger
+JS_EXPORT_API(void)
+JSPrincipals::dump()
+{
+    if (debugToken == nsJSPrincipals::DEBUG_TOKEN) {
+        static_cast<nsJSPrincipals *>(this)->dumpImpl();
+    } else if (debugToken == mozilla::dom::workers::kJSPrincipalsDebugToken) {
+        fprintf(stderr, "Web Worker principal singleton (%p)\n", this);
+    } else {
+        fprintf(stderr,
+                "!!! JSPrincipals (%p) is not nsJSPrincipals instance - bad token: "
+                "actual=0x%x expected=0x%x\n",
+                this, unsigned(debugToken), unsigned(nsJSPrincipals::DEBUG_TOKEN));
+    }
+}
+
+#endif