ozone: Add overlay candidate implementation that queries support via IPC

ui/ozone/platform/drm/host/drm_overlay_manager.h

Index: ui/ozone/platform/drm/host/drm_overlay_manager.h
diff --git a/ui/ozone/platform/drm/host/drm_overlay_manager.h b/ui/ozone/platform/drm/host/drm_overlay_manager.h
index e02ee30081cd2bd0ed56aec1e7f26e724e437488..acb3b9ec774541663fb3242ae86bb3c8032900aa 100644
--- a/ui/ozone/platform/drm/host/drm_overlay_manager.h
+++ b/ui/ozone/platform/drm/host/drm_overlay_manager.h
@@ -5,25 +5,27 @@
 #ifndef UI_OZONE_PLATFORM_DRM_HOST_DRM_OVERLAY_MANAGER_H_
 #define UI_OZONE_PLATFORM_DRM_HOST_DRM_OVERLAY_MANAGER_H_
 
-#include "base/memory/scoped_ptr.h"
 #include "ui/ozone/public/overlay_manager_ozone.h"
 
 namespace ui {
 
+class DrmGpuPlatformSupportHost;
+
 class DrmOverlayManager : public OverlayManagerOzone {
  public:
-  DrmOverlayManager(bool allow_surfaceless);
+  DrmOverlayManager(bool allow_surfaceless,
+                    DrmGpuPlatformSupportHost* platform_support_host);
   ~DrmOverlayManager() override;
 
   // OverlayManagerOzone:
-  OverlayCandidatesOzone* GetOverlayCandidates(
+  scoped_ptr<OverlayCandidatesOzone> GetOverlayCandidates(
       gfx::AcceleratedWidget w) override;
   bool CanShowPrimaryPlaneAsOverlay() override;
 
  private:
+  DrmGpuPlatformSupportHost* platform_support_host_;
   bool allow_surfaceless_;
-
-  scoped_ptr<OverlayCandidatesOzone> candidates_;
+  bool is_supported_;
 
   DISALLOW_COPY_AND_ASSIGN(DrmOverlayManager);
 };