Load extensions features file separately when needed

chrome/renderer/extensions/dispatcher.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/renderer/extensions/dispatcher.h"
 
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string_piece.h"
@@ skipping 664 matching lines @@
     ModuleSystem* module_system,
     ChromeV8Context* context,
     v8::Handle<v8::Context> v8_context) {
   std::set<std::string> apis =
       ExtensionAPI::GetSharedInstance()->GetAllAPINames();
   for (std::set<std::string>::iterator it = apis.begin();
        it != apis.end(); ++it) {
     const std::string& api_name = *it;
 
     Feature* feature =
-        BaseFeatureProvider::GetAPIFeatures()->GetFeature(api_name);
+        BaseFeatureProvider::GetFeaturesByName("api")->GetFeature(api_name);
     if (feature && feature->IsInternal())
       continue;
 
     std::vector<std::string> split;
     base::SplitString(api_name, '.', &split);
 
     v8::Handle<v8::Object> bind_object = GetOrCreateChrome(v8_context);
     for (size_t i = 0; i < split.size() - 1; ++i)
       bind_object = GetOrCreateObject(bind_object, split[i]);
 
@@ skipping 678 matching lines @@
     std::string error_msg = base::StringPrintf(kMessage, function_name.c_str());
     v8::ThrowException(
         v8::Exception::Error(v8::String::New(error_msg.c_str())));
     return false;
   }
 
   return true;
 }
 
 }  // namespace extensions