Validate hash_sha256 checksum on .crx update.

chrome/browser/extensions/updater/extension_updater.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_UPDATER_H_
 #define CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_UPDATER_H_
 
 #include <list>
 #include <map>
 #include <set>
@@ skipping 119 matching lines @@
 
   // Stop the timer to prevent scheduled updates for testing.
   void StopTimerForTesting();
 
  private:
   friend class ExtensionUpdaterTest;
   friend class ExtensionUpdaterFileHandler;
 
   // FetchedCRXFile holds information about a CRX file we fetched to disk,
   // but have not yet installed.
-  struct FetchedCRXFile {
+  struct FetchedCRXFile : public CRXFileInfo {

[asargent_no_longer_on_chrome, 2015/02/03 00:42:55]

I think we'd be better off using composition (have a FetchedCRXFile member
variable) instead of inheritance here.

See style guide entry which encourages this:

http://google-styleguide.googlecode.com/svn/trunk/cppguide.html#Inheritance

     FetchedCRXFile();
-    FetchedCRXFile(const std::string& id,
-                   const base::FilePath& path,
+    FetchedCRXFile(const CRXFileInfo& file,
                    bool file_ownership_passed,
                    const std::set<int>& request_ids);
     ~FetchedCRXFile();
 
-    std::string extension_id;
-    base::FilePath path;
     bool file_ownership_passed;
     std::set<int> request_ids;
   };
 
   struct InProgressCheck {
     InProgressCheck();
     ~InProgressCheck();
 
     bool install_immediately;
     FinishedCallback callback;
@@ skipping 31 matching lines @@
   void TimerFired();
 
   // Posted by CheckSoon().
   void DoCheckSoon();
 
   // Implementation of ExtensionDownloaderDelegate.
   void OnExtensionDownloadFailed(const std::string& id,
                                  Error error,
                                  const PingResult& ping,
                                  const std::set<int>& request_ids) override;
-  void OnExtensionDownloadFinished(const std::string& id,
-                                   const base::FilePath& path,
+  void OnExtensionDownloadFinished(const CRXFileInfo& file,
                                    bool file_ownership_passed,
                                    const GURL& download_url,
                                    const std::string& version,
                                    const PingResult& ping,
                                    const std::set<int>& request_id) override;
   bool GetPingDataForExtension(const std::string& id,
                                ManifestFetchData::PingData* ping_data) override;
   std::string GetUpdateUrlData(const std::string& id) override;
   bool IsExtensionPending(const std::string& id) override;
   bool GetExtensionExistingVersion(const std::string& id,
@@ skipping 78 matching lines @@
   std::set<std::string> forced_updates_;
 
   base::WeakPtrFactory<ExtensionUpdater> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionUpdater);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_UPDATER_EXTENSION_UPDATER_H_