ozone: Introduce ClientPixmap and ClientPixmapFactory for non-GPU processes.

ui/ozone/platform/caca/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/linux/pkg_config.gni")
 
 source_set("caca") {
   sources = [
     "caca_event_source.cc",
     "caca_event_source.h",
     "caca_window.cc",
     "caca_window.h",
     "caca_window_manager.cc",
     "caca_window_manager.h",
+    "native_pixmap_manager_caca.cc",
+    "native_pixmap_manager_caca.h",
     "ozone_platform_caca.cc",
     "ozone_platform_caca.h",
     "scoped_caca_types.cc",
     "scoped_caca_types.h",
   ]
 
   deps = [
     "//base",
     "//skia",
     "//ui/events/ozone:events_ozone_layout",
     "//ui/events/platform",
     "//ui/gfx/geometry",
   ]
 
   configs += [ ":libcaca" ]
 }
 
 pkg_config("libcaca") {
   packages = [ "caca" ]
 }