Split feature definitions into extensions and chrome features.

extensions/common/features/feature_provider.cc

 // Copyright 2013 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 "extensions/common/features/feature_provider.h"
 
+#include <map>
+
 #include "base/basictypes.h"
+#include "base/lazy_instance.h"
+#include "base/memory/linked_ptr.h"
 #include "extensions/common/extensions_client.h"
 
 namespace extensions {
 
+namespace {
+
+class Static {
+ public:
+  FeatureProvider* GetFeatures(const std::string& name) const {
+    FeatureProviderMap::const_iterator it = feature_providers_.find(name);
+    CHECK(it != feature_providers_.end());
+    return it->second.get();
+  }
+
+ private:
+  friend struct base::DefaultLazyInstanceTraits<Static>;
+
+  Static() {
+    ExtensionsClient* client = ExtensionsClient::Get();
+    feature_providers_["api"] =
+        make_linked_ptr(client->CreateFeatureProvider("api").release());
+    feature_providers_["manifest"] =
+        make_linked_ptr(client->CreateFeatureProvider("manifest").release());
+    feature_providers_["permission"] =
+        make_linked_ptr(client->CreateFeatureProvider("permission").release());
+  }
+
+  typedef std::map<std::string, linked_ptr<FeatureProvider> >
+      FeatureProviderMap;
+
+  FeatureProviderMap feature_providers_;
+};
+
+base::LazyInstance<Static> g_static = LAZY_INSTANCE_INITIALIZER;
+
+}  // namespace
+
 // static
 FeatureProvider* FeatureProvider::GetByName(const std::string& name) {
-  return ExtensionsClient::Get()->GetFeatureProviderByName(name);
+  return g_static.Get().GetFeatures(name);
 }
 
 // static
 FeatureProvider* FeatureProvider::GetAPIFeatures() {
   return GetByName("api");
 }
 
 // static
 FeatureProvider* FeatureProvider::GetManifestFeatures() {
   return GetByName("manifest");
 }
 
 // static
 FeatureProvider* FeatureProvider::GetPermissionFeatures() {
   return GetByName("permission");
 }
 
 }  // namespace extensions