Don't block shared_module extensions by the policy blacklist.

chrome/browser/extensions/standard_management_policy_provider.cc

 // Copyright 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.
 
 #include "chrome/browser/extensions/standard_management_policy_provider.h"
 
 #include <string>
 
 #include "base/logging.h"
 #include "base/strings/string16.h"
@@ skipping 58 matching lines @@
 #endif
 }
 
 bool StandardManagementPolicyProvider::UserMayLoad(
     const Extension* extension,
     base::string16* error) const {
   // Component extensions are always allowed.
   if (Manifest::IsComponentLocation(extension->location()))
     return true;
 
+  // Shared modules are always allowed too: they only contain resources that
+  // are used by other extensions. The extension that depends on the shared
+  // module may be filtered by policy.
+  if (extension->is_shared_module())
+    return true;
+
   ExtensionManagement::InstallationMode installation_mode =
       settings_->GetInstallationMode(extension->id());
 
   // Force-installed extensions cannot be overwritten manually.
   if (!Manifest::IsPolicyLocation(extension->location()) &&
       installation_mode == ExtensionManagement::INSTALLATION_FORCED) {
     return ReturnLoadError(extension, error);
   }
 
   // Check whether the extension type is allowed.
@@ skipping 57 matching lines @@
       *error = l10n_util::GetStringFUTF16(
           IDS_EXTENSION_CANT_UNINSTALL_POLICY_REQUIRED,
           base::UTF8ToUTF16(extension->name()));
     }
     return true;
   }
   return false;
 }
 
 }  // namespace extensions