When extension is blacklisted by admin policy, it should be removed if alread...

chrome/browser/extensions/extension_prefs.cc

 // Copyright (c) 2010 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/browser/extensions/extension_prefs.h"
 
 #include "base/string_util.h"
 #include "base/string_number_conversions.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/common/extensions/extension.h"
@@ skipping 223 matching lines @@
 }
 
 bool ExtensionPrefs::IsExtensionBlacklisted(const std::string& extension_id) {
   return ReadExtensionPrefBoolean(extension_id, kPrefBlacklist);
 }
 
 bool ExtensionPrefs::IsExtensionAllowedByPolicy(
     const std::string& extension_id) {
   std::string string_value;
 
+  const ListValue* blacklist = prefs_->GetList(kExtensionInstallDenyList);
+  if (!blacklist || blacklist->empty())
+    return true;
+
   // Check the whitelist first.
   const ListValue* whitelist = prefs_->GetList(kExtensionInstallAllowList);
   if (whitelist) {
     for (ListValue::const_iterator it = whitelist->begin();
          it != whitelist->end(); ++it) {
       if (!(*it)->GetAsString(&string_value))
         LOG(WARNING) << "Failed to read whitelist string.";
       else if (string_value == extension_id)
         return true;
     }
   }
 
   // Then check the blacklist (the admin blacklist, not the Google blacklist).
-  const ListValue* blacklist = prefs_->GetList(kExtensionInstallDenyList);
   if (blacklist) {
     for (ListValue::const_iterator it = blacklist->begin();
          it != blacklist->end(); ++it) {
       if (!(*it)->GetAsString(&string_value)) {
         LOG(WARNING) << "Failed to read blacklist string.";
       } else {
         if (string_value == "*")
           return false;  // Only whitelisted extensions are allowed.
         if (string_value == extension_id)
           return false;
@@ skipping 525 matching lines @@
 
 // static
 void ExtensionPrefs::RegisterUserPrefs(PrefService* prefs) {
   prefs->RegisterDictionaryPref(kExtensionsPref);
   prefs->RegisterListPref(kExtensionToolbar);
   prefs->RegisterIntegerPref(prefs::kExtensionToolbarSize, -1);
   prefs->RegisterDictionaryPref(kExtensionsBlacklistUpdate);
   prefs->RegisterListPref(kExtensionInstallAllowList);
   prefs->RegisterListPref(kExtensionInstallDenyList);
 }