Add support for command line switches to Features, and as proof that it works,

extensions/common/features/feature.cc

 // 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.
 
 #include "extensions/common/features/feature.h"
 
 #include <map>
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "extensions/common/extension.h"
+#include "extensions/common/manifest.h"
 
 namespace extensions {
 
 // static
 Feature::Platform Feature::GetCurrentPlatform() {
 #if defined(OS_CHROMEOS)
   return CHROMEOS_PLATFORM;
 #elif defined(OS_LINUX)
   return LINUX_PLATFORM;
 #elif defined(OS_MACOSX)
@@ skipping 12 matching lines @@
 }
 
 Feature::Availability Feature::IsAvailableToExtension(
     const Extension* extension) {
   return IsAvailableToManifest(extension->id(),
                                extension->GetType(),
                                extension->location(),
                                extension->manifest_version());
 }
 
+Feature::Availability Feature::IsAvailableToEnvironment() const {
+  return IsAvailableToManifest("",  // extension_id
+                               Manifest::TYPE_UNKNOWN,
+                               Manifest::INVALID_LOCATION,
+                               -1);  // manifest_version
+}
+
 Feature::Feature() : no_parent_(false) {}
 
 Feature::~Feature() {}
 
 }  // namespace extensions