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

extensions/common/features/simple_feature.h

 // 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.
 
 #ifndef EXTENSIONS_COMMON_FEATURES_SIMPLE_FEATURE_H_
 #define EXTENSIONS_COMMON_FEATURES_SIMPLE_FEATURE_H_
 
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/callback_forward.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/linked_ptr.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/values.h"
 #include "extensions/common/extension.h"
 #include "extensions/common/features/feature.h"
 #include "extensions/common/features/simple_feature_filter.h"
 #include "extensions/common/manifest.h"
 
 namespace extensions {
 
 class SimpleFeature : public Feature {
  public:
   SimpleFeature();
   ~SimpleFeature() override;
 
   // Similar to Manifest::Location, these are the classes of locations
-  // supported in feature files; "component" implies
-  // COMPONENT/EXTERNAL_COMPONENT manifest location types, etc.
+  // supported in feature files.
   //
   // This is only public for testing. Production code should never access it,
   // nor should it really have any reason to access the SimpleFeature class
   // directly, it should be dealing with the Feature interface.
   enum Location {
     UNSPECIFIED_LOCATION,
     COMPONENT_LOCATION,
+    EXTERNAL_COMPONENT_LOCATION,
     POLICY_LOCATION,
   };
 
   // Accessors defined for testing. See comment above about not directly using
   // SimpleFeature in production code.
   std::set<std::string>* blacklist() { return &blacklist_; }
   std::set<std::string>* whitelist() { return &whitelist_; }
   std::set<Manifest::Type>* extension_types() { return &extension_types_; }
   std::set<Context>* contexts() { return &contexts_; }
   Location location() const { return location_; }
@@ skipping 102 matching lines @@
 
   typedef std::vector<linked_ptr<SimpleFeatureFilter> > FilterList;
   FilterList filters_;
 
   DISALLOW_COPY_AND_ASSIGN(SimpleFeature);
 };
 
 }  // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_FEATURES_SIMPLE_FEATURE_H_