Fix install verification for sideloaded extensions without update urls

chrome/browser/extensions/install_signer.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_INSTALL_SIGNER_H_
 #define CHROME_BROWSER_EXTENSIONS_INSTALL_SIGNER_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 20 matching lines @@
   // The set of ids that have been signed.
   ExtensionIdSet ids;
 
   // Both of these are just arrays of bytes, NOT base64-encoded.
   std::string salt;
   std::string signature;
 
   // The date that the signature should expire, in YYYY-MM-DD format.
   std::string expire_date;
 
-  // The time this signature was obtained from the server.
+  // The time this signature was obtained from the server. Note that this
+  // is computed locally and *not* signed by the server key.
   base::Time timestamp;
 
+  // The set of ids that the server indicated were invalid (ie not signed).
+  // Note that this is computed locally and *not* signed by the signature.
+  ExtensionIdSet invalid_ids;
+
   InstallSignature();
   ~InstallSignature();
 
   // Helper methods for serialization to/from a base::DictionaryValue.
   void ToValue(base::DictionaryValue* value) const;
 
   static scoped_ptr<InstallSignature> FromValue(
       const base::DictionaryValue& value);
 };
 
@@ skipping 60 matching lines @@
 
   // The time the request to the server was started.
   base::Time request_start_time_;
 
   DISALLOW_COPY_AND_ASSIGN(InstallSigner);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_INSTALL_SIGNER_H_