Revert of gpu: Use ANDROID_native_fence_sync instead of ARM_implicit_external_sync.

ui/ozone/platform/drm/gpu/gbm_surfaceless.h

 // 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.
 
 #ifndef UI_OZONE_PLATFORM_DRM_GPU_GBM_SURFACELESS_H_
 #define UI_OZONE_PLATFORM_DRM_GPU_GBM_SURFACELESS_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 58 matching lines @@
     bool ScheduleOverlayPlanes(gfx::AcceleratedWidget widget);
     void Flush();
 
     bool ready = false;
     std::vector<gl::GLSurfaceOverlay> overlays;
     SwapCompletionCallback callback;
   };
 
   void SubmitFrame();
 
-  EGLSyncKHR InsertFence(bool native);
+  EGLSyncKHR InsertFence(bool implicit);
   void FenceRetired(EGLSyncKHR fence, PendingFrame* frame);
 
   void SwapCompleted(const SwapCompletionCallback& callback,
                      gfx::SwapResult result);
 
   GbmSurfaceFactory* surface_factory_;
   std::unique_ptr<DrmWindowProxy> window_;
   std::vector<OverlayPlane> planes_;
 
   // The native surface. Deleting this is allowed to free the EGLNativeWindow.
   gfx::AcceleratedWidget widget_;
   std::unique_ptr<gfx::VSyncProvider> vsync_provider_;
   std::vector<std::unique_ptr<PendingFrame>> unsubmitted_frames_;
-  bool has_native_fence_sync_;
+  bool has_implicit_external_sync_;
   bool last_swap_buffers_result_ = true;
   bool swap_buffers_pending_ = false;
 
   base::WeakPtrFactory<GbmSurfaceless> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(GbmSurfaceless);
 };
 
 }  // namespace ui
 
 #endif  // UI_OZONE_PLATFORM_DRM_GPU_GBM_SURFACELESS_H_