Move benchmark buck file into benchmark directory

Summary: buck rules are not meant to be in the root buck file but instead next to source files. This diff moves benchmark rule into benchmark folder.

Reviewed By: lucasr

Differential Revision: D3992992

fbshipit-source-id: 34782ff73bbd5b799d83d0f01b553bfab928f1df

benchmark/BUCK

@@ -0,0 +1,27 @@
+# Copyright (c) 2014-present, Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree. An additional grant
+# of patent rights can be found in the PATENTS file in the same directory.
+
+include_defs('//CSSLAYOUT_DEFS')
+
+cxx_binary(
+  name = 'benchmark',
+  srcs = glob(['*.c']),
+  headers = subdir_glob([('', '*.h')]),
+  header_namespace = '',
+  compiler_flags = [
+    '-fno-omit-frame-pointer',
+    '-fexceptions',
+    '-Wall',
+    '-Werror',
+    '-O3',
+    '-std=c11',
+  ],
+  deps = [
+    csslayout_dep(':CSSLayout'),
+  ],
+  visibility = ['PUBLIC'],
+)