PPAPI/NaCl: Make NaClIPCAdapter transfer handles more generally

ppapi/shared_impl/host_resource.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ppapi/shared_impl/host_resource.h"
+
+namespace ppapi {
+
+HostResource::HostResource() : instance_(0), host_resource_(0) {
+}
+
+// static
+HostResource HostResource::MakeInstanceOnly(PP_Instance instance) {
+  HostResource resource;
+  resource.SetHostResource(instance, 0);
+  return resource;
+}
+
+void HostResource::SetHostResource(PP_Instance instance, PP_Resource resource) {
+  instance_ = instance;
+  host_resource_ = resource;
+}
+
+}  // namespace ppapi
+