Run clang-modernize -use-nullptr over src/extensions/.

extensions/common/api/sockets/sockets_manifest_handler.cc

Index: extensions/common/api/sockets/sockets_manifest_handler.cc
diff --git a/extensions/common/api/sockets/sockets_manifest_handler.cc b/extensions/common/api/sockets/sockets_manifest_handler.cc
index 113dc6eca5a68ae122a1bc7a04cb4a19d526c0a8..cc2ffa9dafb517176757dfeab26a513ecf2f49d2 100644
--- a/extensions/common/api/sockets/sockets_manifest_handler.cc
+++ b/extensions/common/api/sockets/sockets_manifest_handler.cc
@@ -17,7 +17,7 @@ SocketsManifestHandler::~SocketsManifestHandler() {}
 
 bool SocketsManifestHandler::Parse(Extension* extension,
                                    base::string16* error) {
-  const base::Value* sockets = NULL;
+  const base::Value* sockets = nullptr;
   CHECK(extension->manifest()->Get(manifest_keys::kSockets, &sockets));
   scoped_ptr<SocketsManifestData> data =
       SocketsManifestData::FromValue(*sockets, error);
@@ -37,7 +37,7 @@ ManifestPermission* SocketsManifestHandler::CreateInitialRequiredPermission(
   SocketsManifestData* data = SocketsManifestData::Get(extension);
   if (data)
     return data->permission()->Clone();
-  return NULL;
+  return nullptr;
 }
 
 const std::vector<std::string> SocketsManifestHandler::Keys() const {