Hardware overlay support

Enable hardware overlay support for camera and video playback use cases
diff --git a/camera/libcameraservice/CameraService.h b/camera/libcameraservice/CameraService.h
index ea93789..8a49fa6 100644
--- a/camera/libcameraservice/CameraService.h
+++ b/camera/libcameraservice/CameraService.h
@@ -189,6 +189,10 @@
                     sp<CameraHardwareInterface> mHardware;
                     pid_t                       mClientPid;
                     bool                        mUseOverlay;
+
+                    sp<OverlayRef>              mOverlayRef;
+                    int                         mOverlayW;
+                    int                         mOverlayH;
     };
 
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