ozone: Create GbmBuffers from fourcc formats and gbm flags.

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

 // 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.
 
+#include <drm_fourcc.h>
 #include <stddef.h>
 #include <stdint.h>
 
 #include <utility>
 
 #include "base/macros.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/ozone/platform/drm/gpu/crtc_controller.h"
 #include "ui/ozone/platform/drm/gpu/drm_device_generator.h"
 #include "ui/ozone/platform/drm/gpu/drm_device_manager.h"
@@ skipping 477 matching lines @@
   window = screen_manager_->RemoveWindow(1);
   window->Shutdown();
 }
 
 TEST_F(ScreenManagerTest, EnableControllerWhenWindowHasBuffer) {
   std::unique_ptr<ui::DrmWindow> window(
       new ui::DrmWindow(1, device_manager_.get(), screen_manager_.get()));
   window->Initialize(buffer_generator_.get());
   window->SetBounds(GetPrimaryBounds());
   scoped_refptr<ui::ScanoutBuffer> buffer = buffer_generator_->Create(
-      drm_, gfx::BufferFormat::BGRA_8888, GetPrimaryBounds().size());
+      drm_, DRM_FORMAT_XRGB8888, GetPrimaryBounds().size());

[tfiga, 2016/12/06 07:20:37]

Shouldn't the new format be DRM_FORMAT_ARGB8888?

[Daniele Castagna, 2016/12/06 18:31:10]

At this point Chrome doesn't support overlays with alpha. That means if a gfx
format with alpha arrives here we know we can discard the alpha channel and we
use a fourcc format without alpha to create the framebuffer. You can see that in
drm_util.cc GetFourCCFormatForFramebuffer.

Since we changed the gbmbuffer format from gfx::BufferFormat to a fourcc format,
this change reflects that.

   window->SchedulePageFlip(
       std::vector<ui::OverlayPlane>(1, ui::OverlayPlane(buffer)),
       base::Bind(&EmptySwapCallback));
   screen_manager_->AddWindow(1, std::move(window));
 
   screen_manager_->AddDisplayController(drm_, kPrimaryCrtc, kPrimaryConnector);
   screen_manager_->ConfigureDisplayController(
       drm_, kPrimaryCrtc, kPrimaryConnector, GetPrimaryBounds().origin(),
       kDefaultMode);
 
   EXPECT_EQ(buffer->GetFramebufferId(), drm_->current_framebuffer());
 
   window = screen_manager_->RemoveWindow(1);
   window->Shutdown();
 }