[Extensions] Remove ChromeV8Context and DispatcherDelegate::CreateScriptContext.

ChromeV8Context was a vacuous override, it's just a ScriptContext, and by
replacing instances of ScriptContext the delegate method can be deleted. It
also led me to deleting Feature::CreateAvailability which referenced
ChromeV8Context for some reason.

R=rockot@chromium.org

Review URL: https://codereview.chromium.org/995913002

Cr-Commit-Position: refs/heads/master@{#319976}

4 files changed, 6 insertions, 18 deletions

diff --git a/extensions/common/features/feature.cc b/extensions/common/features/feature.cc
index 8fadf4f..21aa289 100644
--- a/extensions/common/features/feature.cc
+++ b/extensions/common/features/feature.cc
@@ -30,12 +30,6 @@ Feature::Platform Feature::GetCurrentPlatform() {
 #endif
 }
 
-// static
-Feature::Availability Feature::CreateAvailability(AvailabilityResult result,
-                                                  const std::string& message) {
-  return Availability(result, message);
-}
-
 Feature::Availability Feature::IsAvailableToExtension(
     const Extension* extension) const {
   return IsAvailableToManifest(extension->id(),
diff --git a/extensions/common/features/feature.h b/extensions/common/features/feature.h
index 1e476c8..304f6cb 100644
--- a/extensions/common/features/feature.h
+++ b/extensions/common/features/feature.h
@@ -80,6 +80,9 @@ class Feature {
   // message in cases where the feature is not available.
   class Availability {
    public:
+    Availability(AvailabilityResult result, const std::string& message)
+        : result_(result), message_(message) {}
+
     AvailabilityResult result() const { return result_; }
     bool is_available() const { return result_ == IS_AVAILABLE; }
     const std::string& message() const { return message_; }
@@ -88,10 +91,6 @@ class Feature {
     friend class SimpleFeature;
     friend class Feature;
 
-    // Instances should be created via Feature::CreateAvailability.
-    Availability(AvailabilityResult result, const std::string& message)
-        : result_(result), message_(message) { }
-
     const AvailabilityResult result_;
     const std::string message_;
   };
@@ -99,12 +98,6 @@ class Feature {
   Feature();
   virtual ~Feature();
 
-  // Used by ChromeV8Context until the feature system is fully functional.
-  // TODO(kalman): This is no longer used by ChromeV8Context, so what is the
-  // comment trying to say?
-  static Availability CreateAvailability(AvailabilityResult result,
-                                         const std::string& message);
-
   const std::string& name() const { return name_; }
   void set_name(const std::string& name) { name_ = name; }
   bool no_parent() const { return no_parent_; }
diff --git a/extensions/common/features/simple_feature.h b/extensions/common/features/simple_feature.h
index 395a26c..a5bc270 100644
--- a/extensions/common/features/simple_feature.h
+++ b/extensions/common/features/simple_feature.h
@@ -124,6 +124,7 @@ class SimpleFeature : public Feature {
                          const std::set<std::string>& list);
 
  protected:
+  // Handy utilities which construct the correct availability message.
   Availability CreateAvailability(AvailabilityResult result) const;
   Availability CreateAvailability(AvailabilityResult result,
                                   Manifest::Type type) const;
diff --git a/extensions/common/features/simple_feature_filter.cc b/extensions/common/features/simple_feature_filter.cc
index 77343f1..623c49c 100644
--- a/extensions/common/features/simple_feature_filter.cc
+++ b/extensions/common/features/simple_feature_filter.cc
@@ -22,7 +22,7 @@ Feature::Availability SimpleFeatureFilter::IsAvailableToContext(
     Feature::Context context,
     const GURL& url,
     Feature::Platform platform) const {
-  return Feature::CreateAvailability(Feature::IS_AVAILABLE, std::string());
+  return Feature::Availability(Feature::IS_AVAILABLE, std::string());
 }
 
 Feature::Availability SimpleFeatureFilter::IsAvailableToManifest(
@@ -31,7 +31,7 @@ Feature::Availability SimpleFeatureFilter::IsAvailableToManifest(
     Manifest::Location location,
     int manifest_version,
     Feature::Platform platform) const {
-  return Feature::CreateAvailability(Feature::IS_AVAILABLE, std::string());
+  return Feature::Availability(Feature::IS_AVAILABLE, std::string());
 }
 
 }  // namespace extensions