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

chrome/browser/extensions/updater/extension_downloader.h

Index: chrome/browser/extensions/updater/extension_downloader.h
diff --git a/chrome/browser/extensions/updater/extension_downloader.h b/chrome/browser/extensions/updater/extension_downloader.h
index 628f4b86362f76c683b1135aab861d20e352332a..74058607b3abf95dbf359774a74b5de5ebd09b77 100644
--- a/chrome/browser/extensions/updater/extension_downloader.h
+++ b/chrome/browser/extensions/updater/extension_downloader.h
@@ -85,10 +85,12 @@ class ExtensionDownloader : public net::URLFetcherDelegate {
           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