Support extension update dwnloads which require auth

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 af60d67ed878a6d62bd4e6cf2e82515cc81d5749..a40427da068a7daf901ac88af19dd33419202bcb 100644
--- a/chrome/browser/extensions/updater/extension_downloader.h
+++ b/chrome/browser/extensions/updater/extension_downloader.h
@@ -129,6 +129,9 @@ class ExtensionDownloader : public net::URLFetcherDelegate {
     std::string package_hash;
     std::string version;
     std::set<int> request_ids;
+
+    // Indicates whether or not the fetch is known to require credentials.
+    bool is_protected;
   };
 
   // Helper for AddExtension() and AddPendingExtension().