Unrevert r141537: Add extensions::StateStore and use that instead of

chrome/browser/extensions/state_store.cc

Index: chrome/browser/extensions/state_store.cc
diff --git a/chrome/browser/extensions/state_store.cc b/chrome/browser/extensions/state_store.cc
new file mode 100644
index 0000000000000000000000000000000000000000..69d432e3d4fdb1d981ec3c480c570041b9137296
--- /dev/null
+++ b/chrome/browser/extensions/state_store.cc
@@ -0,0 +1,75 @@
+// 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 "chrome/browser/extensions/state_store.h"
+
+#include "chrome/common/chrome_notification_types.h"
+#include "chrome/common/extensions/extension.h"
+#include "content/public/browser/notification_service.h"
+#include "content/public/browser/notification_types.h"
+
+namespace {
+
+std::string GetFullKey(const std::string& extension_id,
+                       const std::string& key) {
+  return extension_id + "." + key;
+}
+
+}  // namespace
+
+namespace extensions {
+
+StateStore::StateStore(Profile* profile, const FilePath& db_path)
+    : store_(db_path) {
+  registrar_.Add(this, chrome::NOTIFICATION_EXTENSION_INSTALLED,
+                 content::Source<Profile>(profile));
+  registrar_.Add(this, chrome::NOTIFICATION_EXTENSION_UNINSTALLED,
+                 content::Source<Profile>(profile));
+}
+
+StateStore::~StateStore() {
+}
+
+void StateStore::RegisterKey(const std::string& key) {
+  registered_keys_.insert(key);
+}
+
+void StateStore::GetExtensionValue(const std::string& extension_id,
+                                   const std::string& key,
+                                   ReadCallback callback) {
+  store_.Get(GetFullKey(extension_id, key), callback);
+}
+
+void StateStore::SetExtensionValue(
+    const std::string& extension_id,
+    const std::string& key,
+    scoped_ptr<base::Value> value) {
+  store_.Set(GetFullKey(extension_id, key), value.Pass());
+}
+
+void StateStore::Observe(int type,
+                         const content::NotificationSource& source,
+                         const content::NotificationDetails& details) {
+  std::string extension_id;
+
+  switch (type) {
+    case chrome::NOTIFICATION_EXTENSION_INSTALLED:
+      extension_id = content::Details<const Extension>(details).ptr()->id();
+      break;
+    case chrome::NOTIFICATION_EXTENSION_UNINSTALLED:
+      extension_id =
+          *content::Details<const std::string>(details).ptr();
+      break;
+    default:
+      NOTREACHED();
+      return;
+  }
+
+  for (std::set<std::string>::iterator key = registered_keys_.begin();
+       key != registered_keys_.end(); ++key) {
+    store_.Remove(GetFullKey(extension_id, *key));
+  }
+}
+
+}  // namespace extensions