gn format '.gni' files.

third_party/WebKit/Source/bindings/core/core.gni

 # Copyright 2014 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.
 
 # FIXME: factor out bindings_core http://crbug.com/358074
 import("//third_party/WebKit/Source/bindings/bindings.gni")
 import("//third_party/WebKit/Source/core/core.gni")
 
 bindings_core_output_dir = "$bindings_output_dir/core"
 
 # Global constructors
 core_global_constructors_original_interfaces = [
   "Window",
   "SharedWorkerGlobalScope",
   "DedicatedWorkerGlobalScope",
 ]
 
 core_global_constructors_generated_idl_files = []
-foreach (interface, core_global_constructors_original_interfaces) {
-  core_global_constructors_generated_idl_files += [
-    "$blink_core_output_dir/${interface}CoreConstructors.idl"
-  ]
+foreach(interface, core_global_constructors_original_interfaces) {
+  core_global_constructors_generated_idl_files +=
+      [ "$blink_core_output_dir/${interface}CoreConstructors.idl" ]
 }