Change namespace from ui to gfx for NativePixmap related code

ui/ozone/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.
 
 import("//build/config/ui.gni")
 import("//ui/ozone/ozone.gni")
 import("//ui/ozone/ozone_extra.gni")
 import("//testing/test.gni")
 
 assert(use_ozone)
@@ skipping 182 matching lines @@
   outputs = [
     constructor_list_cc_file,
   ]
 
   args = [
     "--platform_list=" + rebase_path(platform_list_txt_file, root_build_dir),
     "--output_cc=" + rebase_path(constructor_list_cc_file, root_build_dir),
     "--namespace=ui",
     "--typename=OzonePlatform",
     "--typename=ClientNativePixmapFactory",
+    "--using=gfx::ClientNativePixmapFactory",
     "--include=\"ui/gfx/client_native_pixmap_factory.h\"",
     "--include=\"ui/ozone/public/ozone_platform.h\"",
   ]
 
   deps = [
     ":generate_ozone_platform_list",
   ]
 }
 
 test("ozone_unittests") {
   sources = [
     "run_all_unittests.cc",
   ]
 
   deps = [
     "//base/test:test_support",
     "//testing/gtest",
     "//ui/gfx/geometry",
   ]
 
   # Add tests of platform internals.
   deps += ozone_platform_test_deps
 
   # Platform tests link ozone statically. Make sure we're not getting a
   # 2nd copy of any code via the component.
   assert_no_deps = [ "//ui/ozone" ]
 }