Support static flatbuffers in ContinuousAbsoluteEncoderZeroingEstimator

Change-Id: Ic4dac2ff1084e987b2b20286018821c02967975b
Signed-off-by: James Kuszmaul <jabukuszmaul+collab@gmail.com>
diff --git a/frc971/zeroing/continuous_absolute_encoder.h b/frc971/zeroing/continuous_absolute_encoder.h
index 4994280..5e700ee 100644
--- a/frc971/zeroing/continuous_absolute_encoder.h
+++ b/frc971/zeroing/continuous_absolute_encoder.h
@@ -47,6 +47,8 @@
   virtual flatbuffers::Offset<State> GetEstimatorState(
       flatbuffers::FlatBufferBuilder *fbb) const override;
 
+  void GetEstimatorState(AbsoluteEncoderEstimatorStateStatic *fbs) const;
+
  private:
   struct PositionStruct {
     PositionStruct(const AbsolutePosition &position_buffer)