Make installed_loader UMA less wasteful.

extensions/common/features/simple_feature.cc

 // Copyright 2014 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/simple_feature.h"
 
 #include <map>
 #include <vector>
 
 #include "base/command_line.h"
@@ skipping 145 matching lines @@
     case Manifest::TYPE_LEGACY_PACKAGED_APP:
       return "legacy packaged app";
     case Manifest::TYPE_PLATFORM_APP:
       return "packaged app";
     case Manifest::TYPE_THEME:
       return "theme";
     case Manifest::TYPE_USER_SCRIPT:
       return "user script";
     case Manifest::TYPE_SHARED_MODULE:
       return "shared module";
+    case Manifest::NUM_LOAD_TYPES:
+      NOTREACHED();
   }
   NOTREACHED();
   return "";
 }
 
 // Gets a human-readable name for the given context type, suitable for giving
 // to developers in an error message.
 std::string GetDisplayName(Feature::Context context) {
   switch (context) {
     case Feature::UNSPECIFIED_CONTEXT:
@@ skipping 338 matching lines @@
       return manifest_location == Manifest::COMPONENT;
     case SimpleFeature::POLICY_LOCATION:
       return manifest_location == Manifest::EXTERNAL_POLICY ||
              manifest_location == Manifest::EXTERNAL_POLICY_DOWNLOAD;
   }
   NOTREACHED();
   return false;
 }
 
 }  // namespace extensions