Component updater for FileTypePolicies.

chrome/common/safe_browsing/file_type_policies.cc

 // Copyright 2016 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.
 
 #include "chrome/common/safe_browsing/file_type_policies.h"
 
 #include "base/logging.h"
 #include "base/memory/singleton.h"
 #include "base/metrics/sparse_histogram.h"
 #include "base/strings/string_util.h"
@@ skipping 94 matching lines @@
 
   // Every file type should have exactly one setting, pre-filtered for this
   // platform.
   for (const auto& file_type : new_config->file_types()) {
     if (file_type.platform_settings().size() != 1)
       return UpdateResult::FAILED_WRONG_SETTINGS_COUNT;
   }
 
   // Compare against existing config, if we have one.
   if (config_) {
+    // If versions are equal, we skip the update but it's not really
+    // a failure.
+    if (new_config->version_id() == config_->version_id())
+      return UpdateResult::SKIPPED_VERSION_CHECK_EQUAL;
+
     // Check that version number increases
     if (new_config->version_id() <= config_->version_id())
       return UpdateResult::FAILED_VERSION_CHECK;
 
     // Check that we haven't dropped more than 1/2 the list.
     if (new_config->file_types().size() * 2 < config_->file_types().size())
       return UpdateResult::FAILED_DELTA_CHECK;
   }
 
   // Looks good. Update our internal list.
@@ skipping 95 matching lines @@
 }
 
 DownloadFileType::DangerLevel FileTypePolicies::GetFileDangerLevel(
     const base::FilePath& file) const {
   const std::string ext = CanonicalizedExtension(file);
   AutoLock lock(lock_);
   return PolicyForExtension(ext).platform_settings(0).danger_level();
 }
 
 }  // namespace safe_browsing