Register bindings for blessed web contexts (aka hosted app contexts) by hand

extensions/common/extension_api.h

 // 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.
 
 #ifndef EXTENSIONS_COMMON_EXTENSION_API_H_
 #define EXTENSIONS_COMMON_EXTENSION_API_H_
 
 #include <map>
 #include <string>
 
@@ skipping 47 matching lines @@
   // Creates a completely clean instance. Configure using RegisterSchema() and
   // RegisterDependencyProvider before use.
   ExtensionAPI();
   virtual ~ExtensionAPI();
 
   void RegisterSchemaResource(const std::string& api_name, int resource_id);
 
   void RegisterDependencyProvider(const std::string& name,
                                   FeatureProvider* provider);
 
-  // Returns true if the specified API is available. Returns true if the feature
-  // and all of its dependencies are available to the specified context.
+  // Returns true if the API feature |api| and all of its dependencies are
+  // available in |context|.
+  //
+  // Depending on the configuration of |api| (in _api_features.json), either
+  // |extension| or |url| (or both) may determine its availability, but this is
+  // up to the configuration of the individual feature.
   Feature::Availability IsAvailable(const Feature& api,
                                     const Extension* extension,
                                     Feature::Context context,
                                     const GURL& url);
   // Same as the previous overload, but takes a feature name instead of an
   // object. |api_full_name| can be either a namespace name (like "bookmarks")
   // or a member name (like "bookmarks.create").
   Feature::Availability IsAvailable(const std::string& api_full_name,
                                     const Extension* extension,
                                     Feature::Context context,
@@ skipping 57 matching lines @@
   // FeatureProviders used for resolving dependencies.
   typedef std::map<std::string, FeatureProvider*> FeatureProviderMap;
   FeatureProviderMap dependency_providers_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionAPI);
 };
 
 } // namespace extensions
 
 #endif  // EXTENSIONS_COMMON_EXTENSION_API_H_