Persist sessionStorage on disk.

content/browser/dom_storage/session_storage_namespace_impl.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/browser/dom_storage/session_storage_namespace_impl.h"
 
 #include "content/browser/dom_storage/dom_storage_context_impl.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/notification_service.h"
+#include "content/public/browser/notification_types.h"
 #include "webkit/dom_storage/dom_storage_session.h"
 
 using dom_storage::DomStorageSession;
 
+SessionStorageAssociatedDetails::SessionStorageAssociatedDetails() {
+}
+
+SessionStorageAssociatedDetails::SessionStorageAssociatedDetails(int64 id,
+                                                                 int64 real_id)
+    : id(id), real_id(real_id) {
+}
+
+SessionStorageAssociatedDetails::~SessionStorageAssociatedDetails() {
+}
+
 SessionStorageNamespaceImpl::SessionStorageNamespaceImpl(
     DOMStorageContextImpl* context)
     : session_(new DomStorageSession(context->context())) {
+  session_->AddSessionStorageObserver(id(), this);
 }
 
 int64 SessionStorageNamespaceImpl::id() const {
   return session_->namespace_id();
 }
 
 SessionStorageNamespaceImpl* SessionStorageNamespaceImpl::Clone() {
-  return new SessionStorageNamespaceImpl(session_->Clone());
+  DomStorageSession* new_session = session_->Clone();
+  new_session->AddSessionStorageObserver(new_session->namespace_id(), this);
+  return new SessionStorageNamespaceImpl(new_session);
+}
+
+void SessionStorageNamespaceImpl::OnSessionStorageNamespaceAssociated(
+    int64 real_namespace_id) {
+  if (!content::BrowserThread::CurrentlyOn(content::BrowserThread::UI)) {
+    content::BrowserThread::PostTask(
+        content::BrowserThread::UI, FROM_HERE, base::Bind(
+            &SessionStorageNamespaceImpl::OnSessionStorageNamespaceAssociated,
+            this, real_namespace_id));
+    return;
+  }
+
+  SessionStorageAssociatedDetails details(id(), real_namespace_id);
+  content::NotificationService::current()->Notify(
+      content::NOTIFICATION_SESSION_STORAGE_ASSOCIATED,
+      content::Source<SessionStorageNamespaceImpl>(this),
+      content::Details<SessionStorageAssociatedDetails>(&details));
 }
 
 SessionStorageNamespaceImpl::SessionStorageNamespaceImpl(
     DomStorageSession* clone)
     : session_(clone) {
 }
 
 SessionStorageNamespaceImpl::~SessionStorageNamespaceImpl() {
+  session_->RemoveSessionStorageObserver(session_->namespace_id());
 }