Tease apart ServiceWorkerNetworkProvider from other stuff.

content/child/service_worker/service_worker_network_provider.cc

+// Copyright 2014 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/child/service_worker/service_worker_network_provider.h"
+
+#include "base/atomic_sequence_num.h"
+#include "content/child/child_thread.h"
+#include "content/common/service_worker/service_worker_messages.h"
+
+namespace content {
+
+namespace {
+
+const char kUserDataKey[] = "SWProviderKey";
+
+// Must be unique in the child process.
+int GetNextProviderId() {
+  static base::StaticAtomicSequenceNumber sequence;
+  return sequence.GetNext();  // We start at zero.
+}
+
+}  // namespace
+
+void ServiceWorkerNetworkProvider::AttachToDocumentState(
+    base::SupportsUserData* datasource_userdata,
+    scoped_ptr<ServiceWorkerNetworkProvider> network_provider) {
+  datasource_userdata->SetUserData(&kUserDataKey, network_provider.release());
+}
+
+ServiceWorkerNetworkProvider* ServiceWorkerNetworkProvider::FromDocumentState(
+    base::SupportsUserData* datasource_userdata) {
+  return static_cast<ServiceWorkerNetworkProvider*>(
+      datasource_userdata->GetUserData(&kUserDataKey));
+}
+
+ServiceWorkerNetworkProvider::ServiceWorkerNetworkProvider()
+    : provider_id_(GetNextProviderId()) {
+  if (!ChildThread::current())
+    return;  // May be null in some tests.
+  ChildThread::current()->Send(
+      new ServiceWorkerHostMsg_ProviderCreated(provider_id_));
+}
+
+ServiceWorkerNetworkProvider::~ServiceWorkerNetworkProvider() {
+  if (!ChildThread::current())
+    return;  // May be null in some tests.
+  ChildThread::current()->Send(
+      new ServiceWorkerHostMsg_ProviderDestroyed(provider_id_));
+}
+
+}  // namespace content