XXX test gn format everything

mojo/public/dart/BUILD.gn

 # 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.
 
 group("dart") {
   testonly = true
   deps = [
     ":core",
     ":bindings",
   ]
 }
 
-
 group("core") {
   deps = [
     ":mojo_dart_core",
     ":copy_core_library",
   ]
 }
 
-
 shared_library("mojo_dart_core") {
-  defines = ["DART_SHARED_LIB"]
+  defines = [ "DART_SHARED_LIB" ]
   sources = [
     "src/mojo_dart_core.cc",
   ]
   deps = [
     "//mojo/public/c/environment",
     "//mojo/public/c/system:for_shared_library",
     "//mojo/public/cpp/environment:standalone",
     "//mojo/public/cpp/system",
     "//mojo/public/cpp/utility",
     "//mojo/public/cpp/bindings:callback",
   ]
 }
 
-
 copy("copy_core_library") {
   sources = [
     "$root_out_dir/libmojo_dart_core.so",
   ]
-  outputs = [
-    "$root_out_dir/gen/mojo/public/dart/src/libmojo_dart_core.so"
-  ]
-  deps =[
-    ":mojo_dart_core"
+  outputs = [ "$root_out_dir/gen/mojo/public/dart/src/libmojo_dart_core.so" ]
+  deps = [
+    ":mojo_dart_core",
   ]
 }
 
-
 copy("bindings") {
   sources = [
     "bindings.dart",
     "core.dart",
     "mojo_init.dart",
     "src/buffer.dart",
     "src/client.dart",
     "src/codec.dart",
     "src/data_pipe.dart",
     "src/handle.dart",
     "src/handle_watcher.dart",
     "src/interface.dart",
     "src/message_pipe.dart",
     "src/types.dart",
   ]
-  outputs = [
-    "{{source_gen_dir}}/{{source_file_part}}"
-  ]
-}
+  outputs = [ "{{source_gen_dir}}/{{source_file_part}}" ]
+}