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

ui/ozone/platform/dri/dri_wrapper.h

 // 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.
 
 #ifndef UI_OZONE_PLATFORM_DRI_DRI_WRAPPER_H_
 #define UI_OZONE_PLATFORM_DRI_DRI_WRAPPER_H_
 
 #include <stdint.h>
 
 #include <vector>
 
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/scoped_vector.h"
 #include "base/threading/thread.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/rect_f.h"
 #include "ui/gfx/overlay_transform.h"
 #include "ui/ozone/platform/dri/hardware_display_plane_manager.h"
 #include "ui/ozone/platform/dri/scoped_drm_types.h"
 
 typedef struct _drmEventContext drmEventContext;
 typedef struct _drmModeModeInfo drmModeModeInfo;
 
 struct SkImageInfo;
 
 namespace ui {
 
 class HardwareDisplayPlaneManager;
+class IOHelperThread;
 
 // Wraps DRM calls into a nice interface. Used to provide different
 // implementations of the DRM calls. For the actual implementation the DRM API
 // would be called. In unit tests this interface would be stubbed.
 class DriWrapper {
  public:
   typedef base::Callback<void(unsigned int /* frame */,
                               unsigned int /* seconds */,
                               unsigned int /* useconds */)> PageFlipCallback;
 
-  DriWrapper(const char* device_path, bool use_sync_flips);
+  // TODO(dnicoara) We should be passing a TaskRunner, however we cannot
+  // initialize the thread that early since the Ozone platform (and DriWrapper)
+  // is initializing before the sandbox.
+  DriWrapper(const char* device_path, IOHelperThread* io_thread);
   virtual ~DriWrapper();
 
   // Open device.
   virtual void Initialize();
 
   // Get the CRTC state. This is generally used to save state before using the
   // CRTC. When the user finishes using the CRTC, the user should restore the
   // CRTC to it's initial state. Use |SetCrtc| to restore the state.
   virtual ScopedDrmCrtcPtr GetCrtc(uint32_t crtc_id);
 
@@ skipping 105 matching lines @@
   // after the sandbox is up, thus the late initialization.
   virtual void InitializeIOWatcher();
 
   // The file descriptor associated with this wrapper. All DRM operations will
   // be performed using this FD.
   // TODO(dnicoara) Make this a base::File
   int fd_;
 
   scoped_ptr<HardwareDisplayPlaneManager> plane_manager_;
 
-  // If we need to block when performing page flips this is set to true.
-  bool use_sync_flips_;
-
  private:
   class IOWatcher;
 
   // Path to DRM device.
   const char* device_path_;
 
   // Helper thread to perform IO listener operations.
   // TODO(dnicoara) This should really be supported by the main thread.
   // Alternatively we should have a way to access the IO thread's task runner.
-  base::Thread io_thread_;
+  IOHelperThread* io_thread_;
 
   // Watcher for |fd_| listening for page flip events.
   scoped_refptr<IOWatcher> watcher_;
 
   DISALLOW_COPY_AND_ASSIGN(DriWrapper);
 };
 
 }  // namespace ui
 
 #endif  // UI_OZONE_PLATFORM_DRI_DRI_WRAPPER_H_