Don't group packaged apps in with TYPE_UNKNOWN for update check histograms.

chrome/browser/extensions/updater/extension_downloader.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_DOWNLOADER_H_
 #define CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_DOWNLOADER_H_
 
 #include <deque>
 #include <map>
 #include <set>
@@ skipping 67 matching lines @@
   // These counters are bumped as extensions are added to be fetched. They
   // are then recorded as UMA metrics when all the extensions have been added.
   struct URLStats {
     URLStats()
         : no_url_count(0),
           google_url_count(0),
           other_url_count(0),
           extension_count(0),
           theme_count(0),
           app_count(0),
+          platform_app_count(0),
           pending_count(0) {}
 
     int no_url_count, google_url_count, other_url_count;
-    int extension_count, theme_count, app_count, pending_count;
+    int extension_count, theme_count, app_count, platform_app_count,
+        pending_count;
   };
 
   // We need to keep track of some information associated with a url
   // when doing a fetch.
   struct ExtensionFetch {
     ExtensionFetch();
     ExtensionFetch(const std::string& id, const GURL& url,
                    const std::string& package_hash, const std::string& version);
     ~ExtensionFetch();
 
@@ skipping 94 matching lines @@
 
   // Maps an extension-id to its PingResult data.
   std::map<std::string, ExtensionDownloaderDelegate::PingResult> ping_results_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionDownloader);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_DOWNLOADER_H_