Reduce size of generated extension FeatureProviders.

extensions/common/features/base_feature_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 "extensions/common/features/base_feature_provider.h"
 
+#include <utility>
+
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
 #include "extensions/common/features/feature.h"
 
 namespace extensions {
 
 BaseFeatureProvider::BaseFeatureProvider() {}
 BaseFeatureProvider::~BaseFeatureProvider() {}
 
 const FeatureMap& BaseFeatureProvider::GetAllFeatures() const {
@@ skipping 35 matching lines @@
 
   std::vector<Feature*> result;
   result.reserve(std::distance(first_child, after_children));
   for (FeatureMap::const_iterator it = first_child; it != after_children;
        ++it) {
     result.push_back(it->second.get());
   }
   return result;
 }
 
+void BaseFeatureProvider::AddFeature(base::StringPiece name,
+                                     std::unique_ptr<Feature> feature) {
+  features_[name.as_string()] = std::move(feature);
+}
+
 }  // namespace extensions