Implement API features for the Extension API feature system

chrome/common/extensions/api/extension_api.h

Index: chrome/common/extensions/api/extension_api.h
diff --git a/chrome/common/extensions/api/extension_api.h b/chrome/common/extensions/api/extension_api.h
index 924ee8cb52abd76914f8ef9d7fccbeb4463f0b3c..8a83334f06ce71d6325228245a825add98a53eec 100644
--- a/chrome/common/extensions/api/extension_api.h
+++ b/chrome/common/extensions/api/extension_api.h
@@ -37,7 +37,7 @@ class Feature;
 // WARNING: This class is accessed on multiple threads in the browser process
 // (see ExtensionFunctionDispatcher). No state should be modified after
 // construction.
-class ExtensionAPI : public FeatureProvider {
+class ExtensionAPI {
  public:
   // Returns a single shared instance of this class. This is the typical use
   // case in Chrome.
@@ -88,11 +88,6 @@ class ExtensionAPI : public FeatureProvider {
 
   std::set<std::string> GetAllAPINames();
 
-  // Gets a Feature object describing the API with the specified |full_name|.
-  // This can be either an API namespace (like history, or
-  // experimental.bookmarks), or it can be an individual function or event.
-  virtual Feature* GetFeature(const std::string& full_name) OVERRIDE;
-
   // Splits a full name from the extension API into its API and child name
   // parts. Some examples:
   //
@@ -107,6 +102,9 @@ class ExtensionAPI : public FeatureProvider {
 
   void InitDefaultConfiguration();
 
+  // Gets a feature from any dependency provider registered with ExtensionAPI.
+  Feature* GetFeatureDependency(const std::string& dependency_name);

[not at google - send to devlin, 2013/03/26 00:34:48]

This doesn't appear to be used outside of this class, so it can be private.

[cduvall, 2013/03/26 19:24:05]

It's used in the unit test.

+
  private:
   friend struct DefaultSingletonTraits<ExtensionAPI>;
 
@@ -137,20 +135,9 @@ class ExtensionAPI : public FeatureProvider {
   // Returns true if the API uses the feature system.
   bool UsesFeatureSystem(const std::string& full_name);
 
-  // Gets a feature from any dependency provider.
-  Feature* GetFeatureDependency(const std::string& dependency_name);
-
-  // Adds dependent schemas to |out| as determined by the "dependencies"
-  // property.
-  // TODO(aa): Consider making public and adding tests.
-  void ResolveDependencies(std::set<std::string>* out);
-
-  // Adds any APIs listed in "dependencies" found in the schema for |api_name|
-  // but not in |excluding| to |out|.
-  void GetMissingDependencies(
-      const std::string& api_name,
-      const std::set<std::string>& excluding,
-      std::set<std::string>* out);
+  // Attempts to get a feature from any dependency provider, and returns NULL
+  // if the feature could not be found.
+  Feature* TryGetFeatureDependency(const std::string& dependency_name);
 
   // Checks if an API is *entirely* privileged. This won't include APIs such as
   // "storage" which is entirely unprivileged, nor "extension" which has