Remove kOzoneTestSingleOverlaySupport.

ui/ozone/platform/drm/host/drm_overlay_manager.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_HOST_DRM_OVERLAY_MANAGER_H_
 #define UI_OZONE_PLATFORM_DRM_HOST_DRM_OVERLAY_MANAGER_H_
 
 #include <stdint.h>
 
 #include <vector>
@@ skipping 31 matching lines @@
       gfx::AcceleratedWidget widget);
 
  private:
   void SendOverlayValidationRequest(
       const std::vector<OverlayCheck_Params>& new_params,
       gfx::AcceleratedWidget widget) const;
   bool CanHandleCandidate(
       const OverlayCandidatesOzone::OverlaySurfaceCandidate& candidate,
       gfx::AcceleratedWidget widget) const;
 
-  bool is_supported_;
   GpuThreadAdapter* proxy_;               // Not owned.
   DrmWindowHostManager* window_manager_;  // Not owned.
 
   // List of all OverlayCheck_Params which have been validated in GPU side.
   // Value is set to true if we are waiting for validation results from GPU.
   base::MRUCache<std::vector<OverlayCheck_Params>, bool> cache_;
 
   DISALLOW_COPY_AND_ASSIGN(DrmOverlayManager);
 };
 
 }  // namespace ui
 
 #endif  // UI_OZONE_PLATFORM_DRM_HOST_DRM_OVERLAY_MANAGER_H_