Turn FileDescriptorInfo a collection class

content/public/browser/file_descriptor_info.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 "content/public/browser/file_descriptor_info.h"
+
+namespace content {
+
+FileDescriptorInfo::FileDescriptorInfo() {
+}
+
+FileDescriptorInfo::~FileDescriptorInfo() {
+}
+
+void FileDescriptorInfo::Transfer(int id, base::ScopedFD fd) {
+  AddToMapping(id, fd.get());
+  owned_descriptors_.push_back(new base::ScopedFD(fd.Pass()));
+}
+
+void FileDescriptorInfo::Share(int id, base::PlatformFile fd) {
+  AddToMapping(id, fd);
+}
+
+base::PlatformFile FileDescriptorInfo::GetFDAt(size_t i) const {
+  return descriptors_[i].first;
+}
+
+int FileDescriptorInfo::GetIDAt(size_t i) const {
+  return descriptors_[i].second;
+}
+
+void FileDescriptorInfo::AddToMapping(int id, base::PlatformFile fd) {
+  DCHECK(descriptors_.end() == std::find(descriptors_.begin(),

[mdempsky, 2014/09/22 18:30:51]

This check allows duplicate mappings for a single |id| as long as they map to
different |fd|s. Is that intentional?

+                                         descriptors_.end(),
+                                         std::make_pair(fd, id)));
+  descriptors_.push_back(std::make_pair(fd, id));
+}
+
+}  // namespace content