Add GN build for parts of gpu and ozone.

ui/gfx/x/BUILD.gn

Index: ui/gfx/x/BUILD.gn
diff --git a/ui/gfx/x/BUILD.gn b/ui/gfx/x/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..23d6536e9163d4a8684974ef6a0ef27bd9ee8136
--- /dev/null
+++ b/ui/gfx/x/BUILD.gn
@@ -0,0 +1,21 @@
+# 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.
+
+component("x") {
+  output_name = "gfx_x11"
+  sources = [
+    "x11_atom_cache.cc",
+    "x11_atom_cache.h",
+    "x11_connection.cc",
+    "x11_connection.h",
+    "x11_error_tracker.cc",
+    "x11_error_tracker.h",
+    "x11_types.cc",
+    "x11_types.h",
+  ]
+
+  defines = [ "GFX_IMPLEMENTATION" ]
+  configs += [ "//build/config/linux:x11" ]
+  deps = [ "//base" ]
+}