[Ozone-Dri] Decouple the IO helper thread from DriWrapper

ui/ozone/platform/dri/ozone_platform_gbm.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 "ui/ozone/platform/dri/ozone_platform_gbm.h"
 
 #include <dlfcn.h>
 #include <gbm.h>
 #include <stdlib.h>
 
 #include "base/at_exit.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "ui/base/cursor/ozone/bitmap_cursor_factory_ozone.h"
 #include "ui/events/ozone/device/device_manager.h"
 #include "ui/events/ozone/evdev/event_factory_evdev.h"
 #include "ui/events/ozone/layout/keyboard_layout_engine_manager.h"
 #include "ui/ozone/platform/dri/display_manager.h"
 #include "ui/ozone/platform/dri/dri_cursor.h"
 #include "ui/ozone/platform/dri/dri_gpu_platform_support.h"
 #include "ui/ozone/platform/dri/dri_gpu_platform_support_host.h"
+#include "ui/ozone/platform/dri/dri_helper_thread.h"
 #include "ui/ozone/platform/dri/dri_window.h"
 #include "ui/ozone/platform/dri/dri_window_delegate_manager.h"
 #include "ui/ozone/platform/dri/dri_window_manager.h"
 #include "ui/ozone/platform/dri/gbm_buffer.h"
 #include "ui/ozone/platform/dri/gbm_surface.h"
 #include "ui/ozone/platform/dri/gbm_surface_factory.h"
 #include "ui/ozone/platform/dri/gbm_wrapper.h"
 #include "ui/ozone/platform/dri/native_display_delegate_dri.h"
 #include "ui/ozone/platform/dri/native_display_delegate_proxy.h"
 #include "ui/ozone/platform/dri/scanout_buffer.h"
@@ skipping 109 matching lines @@
     KeyboardLayoutEngineManager::SetKeyboardLayoutEngine(
         make_scoped_ptr(new StubKeyboardLayoutEngine()));
 #endif
     event_factory_ozone_.reset(new EventFactoryEvdev(
         cursor_.get(), device_manager_.get(),
         KeyboardLayoutEngineManager::GetKeyboardLayoutEngine()));
   }
 
   void InitializeGPU() override {
     gl_api_loader_.reset(new GlApiLoader());
+    if (use_surfaceless_)
+      helper_thread_.reset(new DriHelperThread());
+
     // Async page flips are supported only on surfaceless mode.
-    gbm_.reset(new GbmWrapper(kDefaultGraphicsCardPath, !use_surfaceless_));
+    gbm_.reset(new GbmWrapper(kDefaultGraphicsCardPath, helper_thread_.get()));
     gbm_->Initialize();
     buffer_generator_.reset(new GbmBufferGenerator());
     screen_manager_.reset(
         new ScreenManager(gbm_.get(), buffer_generator_.get()));
     window_delegate_manager_.reset(new DriWindowDelegateManager());
     if (!surface_factory_ozone_)
       surface_factory_ozone_.reset(new GbmSurfaceFactory(use_surfaceless_));
 
     surface_factory_ozone_->InitializeGpu(gbm_.get(), screen_manager_.get(),
                                           window_delegate_manager_.get());
     scoped_ptr<NativeDisplayDelegateDri> ndd(
         new NativeDisplayDelegateDri(gbm_.get(), screen_manager_.get()));
     ndd->Initialize();
-    gpu_platform_support_.reset(
-        new DriGpuPlatformSupport(gbm_.get(), window_delegate_manager_.get(),
-                                  screen_manager_.get(), ndd.Pass()));
+    gpu_platform_support_.reset(new DriGpuPlatformSupport(
+        gbm_.get(), window_delegate_manager_.get(), screen_manager_.get(),
+        helper_thread_.get(), ndd.Pass()));
   }
 
  private:
   bool use_surfaceless_;
   scoped_ptr<GlApiLoader> gl_api_loader_;
+  scoped_ptr<DriHelperThread> helper_thread_;
   scoped_ptr<GbmWrapper> gbm_;
   scoped_ptr<GbmBufferGenerator> buffer_generator_;
   scoped_ptr<ScreenManager> screen_manager_;
   scoped_ptr<DeviceManager> device_manager_;
 
   scoped_ptr<GbmSurfaceFactory> surface_factory_ozone_;
   scoped_ptr<BitmapCursorFactoryOzone> cursor_factory_ozone_;
   scoped_ptr<EventFactoryEvdev> event_factory_ozone_;
 
   scoped_ptr<DriGpuPlatformSupport> gpu_platform_support_;
@@ skipping 13 matching lines @@
 };
 
 }  // namespace
 
 OzonePlatform* CreateOzonePlatformGbm() {
   base::CommandLine* cmd = base::CommandLine::ForCurrentProcess();
   return new OzonePlatformGbm(cmd->HasSwitch(switches::kOzoneUseSurfaceless));
 }
 
 }  // namespace ui