Add the basic infrastructure for the Behavior feature type: BehaviorFeature and

extensions/common/features/feature_provider.cc

Index: extensions/common/features/feature_provider.cc
diff --git a/extensions/common/features/feature_provider.cc b/extensions/common/features/feature_provider.cc
index 1923836a91cf5dd71772bb22e68059d0c3e0af1c..9d91ed5ab3055ef52b98ffae0fc079a5782f7009 100644
--- a/extensions/common/features/feature_provider.cc
+++ b/extensions/common/features/feature_provider.cc
@@ -34,6 +34,8 @@ class Static {
         make_linked_ptr(client->CreateFeatureProvider("manifest").release());
     feature_providers_["permission"] =
         make_linked_ptr(client->CreateFeatureProvider("permission").release());
+    feature_providers_["switch"] =
+        make_linked_ptr(client->CreateFeatureProvider("switch").release());
   }
 
   typedef std::map<std::string, linked_ptr<FeatureProvider> >
@@ -66,4 +68,8 @@ const FeatureProvider* FeatureProvider::GetPermissionFeatures() {
   return GetByName("permission");
 }
 
+const FeatureProvider* FeatureProvider::GetSwitchFeatures() {
+  return GetByName("switch");
+}
+
 }  // namespace extensions