Load extensions features file separately when needed

chrome/common/extensions/manifest.cc

 // Copyright (c) 2012 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 "chrome/common/extensions/manifest.h"
 
 #include "base/basictypes.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/stringprintf.h"
@@ skipping 121 matching lines @@
     *error = errors::kPlatformAppNeedsManifestVersion2;
     return false;
   }
 
   // Check every feature to see if its in the manifest. Note that this means
   // we will ignore keys that are not features; we do this for forward
   // compatibility.
   // TODO(aa): Consider having an error here in the case of strict error
   // checking to let developers know when they screw up.
 
-  std::set<std::string> feature_names =
-      BaseFeatureProvider::GetManifestFeatures()->GetAllFeatureNames();
+  BaseFeatureProvider* provider =
+      BaseFeatureProvider::GetFeaturesByName("manifest");
+  std::set<std::string> feature_names = provider->GetAllFeatureNames();
   for (std::set<std::string>::iterator feature_name = feature_names.begin();
        feature_name != feature_names.end(); ++feature_name) {
     // Use Get instead of HasKey because the former uses path expansion.
     if (!value_->Get(*feature_name, NULL))
       continue;
 
-    Feature* feature =
-        BaseFeatureProvider::GetManifestFeatures()->GetFeature(*feature_name);
+    Feature* feature = provider->GetFeature(*feature_name);
     Feature::Availability result = feature->IsAvailableToManifest(
         extension_id_, type_, Feature::ConvertLocation(location_),
         GetManifestVersion());
     if (!result.is_available())
       warnings->push_back(InstallWarning(
           InstallWarning::FORMAT_TEXT, result.message()));
   }
 
   // Also generate warnings for keys that are not features.
   for (base::DictionaryValue::Iterator it(*value_); !it.IsAtEnd();
        it.Advance()) {
-    if (!BaseFeatureProvider::GetManifestFeatures()->GetFeature(it.key())) {
+    if (!provider->GetFeature(it.key())) {
       warnings->push_back(InstallWarning(
           InstallWarning::FORMAT_TEXT,
           base::StringPrintf("Unrecognized manifest key '%s'.",
                              it.key().c_str())));
     }
   }
   return true;
 }
 
 bool Manifest::HasKey(const std::string& key) const {
@@ skipping 67 matching lines @@
     key += components[i];
     if (!CanAccessKey(key))
       return false;
     key += '.';
   }
   return true;
 }
 
 bool Manifest::CanAccessKey(const std::string& key) const {
   Feature* feature =
-      BaseFeatureProvider::GetManifestFeatures()->GetFeature(key);
+      BaseFeatureProvider::GetFeaturesByName("manifest")->GetFeature(key);
   if (!feature)
     return true;
 
   return feature->IsAvailableToManifest(
       extension_id_, type_, Feature::ConvertLocation(location_),
       GetManifestVersion()).is_available();
 }
 
 }  // namespace extensions