Sang's initial CL for moving the file interface out of dev.

ppapi/cpp/file_system.cc

Index: ppapi/cpp/file_system.cc
===================================================================
--- ppapi/cpp/file_system.cc	(revision 0)
+++ ppapi/cpp/file_system.cc	(revision 0)
@@ -0,0 +1,40 @@
+// Copyright (c) 2011 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/cpp/file_system.h"
+
+#include "ppapi/c/pp_errors.h"
+#include "ppapi/c/ppb_file_system.h"
+#include "ppapi/cpp/completion_callback.h"
+#include "ppapi/cpp/file_ref.h"
+#include "ppapi/cpp/module.h"
+#include "ppapi/cpp/module_impl.h"
+
+namespace pp {
+
+namespace {
+
+template <> const char* interface_name<PPB_FileSystem>() {
+  return PPB_FILESYSTEM_INTERFACE;
+}
+
+}  // namespace
+
+FileSystem::FileSystem(Instance* instance,
+                       PP_FileSystemType type) {
+  if (!has_interface<PPB_FileSystem>())
+    return;
+  PassRefFromConstructor(get_interface<PPB_FileSystem>()->Create(
+      instance->pp_instance(), type));
+}
+
+int32_t FileSystem::Open(int64_t expected_size,
+                         const CompletionCallback& cc) {
+  if (!has_interface<PPB_FileSystem>())
+    return PP_ERROR_NOINTERFACE;
+  return get_interface<PPB_FileSystem>()->Open(
+      pp_resource(), expected_size, cc.pp_completion_callback());
+}
+
+}  // namespace pp