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

ui/ozone/platform/drm/gpu/native_pixmap_client_gbm.cc

+// Copyright 2015 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/drm/gpu/native_pixmap_client_gbm.h"
+
+#include "ui/ozone/public/native_pixmap_client.h"
+
+namespace ui {
+
+namespace {
+
+class NativePixmapClientGbm : public NativePixmapClient {
+ public:
+  NativePixmapClientGbm() {}
+  ~NativePixmapClientGbm() override {}
+
+  // NativePixmapClient:
+  void Initialize() override {
+    // TODO(dshwang): get VGEM fd. crbug.com/475633

[dshwang, 2015/06/03 14:11:51]

This method will get VGEM fd from DrmDisplayHostManager in Browser process.
It depends on https://codereview.chromium.org/1151533002/

Render process and Browser process needs different implementation because
NativePixmapClientGbm in Render process needs API mechanism. It might requires
different Initialize methods. Let's discuss more detail in the future CL.

+  }
+
+  std::vector<Configuration> GetSupportedNativePixmapConfigurations()
+      const override {
+    std::vector<Configuration> configurations = {
+        {SurfaceFactoryOzone::BGRA_8888, SurfaceFactoryOzone::SCANOUT},
+        {SurfaceFactoryOzone::RGBX_8888, SurfaceFactoryOzone::SCANOUT}};
+    return configurations;
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(NativePixmapClientGbm);
+};
+
+}  // namespace
+
+NativePixmapClient* CreateNativePixmapClientGbm() {
+  return new NativePixmapClientGbm;
+}
+
+}  // namespace ui