make base::SharedMemoryHandle a class on POSIX.

ui/ozone/platform/wayland/wayland_surface_factory.cc

 // Copyright 2016 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.
 
 #include "ui/ozone/platform/wayland/wayland_surface_factory.h"
 
 #include <fcntl.h>
 #include <sys/mman.h>
 #include <wayland-client.h>
 
@@ skipping 50 matching lines @@
 sk_sp<SkSurface> WaylandCanvasSurface::GetSurface() {
   if (sk_surface_)
     return sk_surface_;
 
   size_t length = size_.width() * size_.height() * 4;
   auto shared_memory = base::WrapUnique(new base::SharedMemory);
   if (!shared_memory->CreateAndMapAnonymous(length))
     return nullptr;
 
   wl::Object<wl_shm_pool> pool(wl_shm_create_pool(
-      connection_->shm(), shared_memory->handle().fd, length));
+      connection_->shm(), shared_memory->handle().GetHandle(), length));
   if (!pool)
     return nullptr;
   wl::Object<wl_buffer> buffer(
       wl_shm_pool_create_buffer(pool.get(), 0, size_.width(), size_.height(),
                                 size_.width() * 4, WL_SHM_FORMAT_ARGB8888));
   if (!buffer)
     return nullptr;
 
   sk_surface_ = SkSurface::MakeRasterDirectReleaseProc(
       SkImageInfo::MakeN32Premul(size_.width(), size_.height()),
@@ skipping 153 matching lines @@
 WaylandSurfaceFactory::CreateNativePixmapFromHandle(
     gfx::AcceleratedWidget widget,
     gfx::Size size,
     gfx::BufferFormat format,
     const gfx::NativePixmapHandle& handle) {
   NOTIMPLEMENTED();
   return nullptr;
 }
 
 }  // namespace ui