message: Mark GetBufferMinAlignment() const
  Like GetBufferPointer() and GetSize(), marks GetBufferMinAlignment function as const
diff: @@ -1219,7 +1219,7 @@ class FlatBufferBuilder {
  /// you call Finish()). You can use this information if you need to embed
  /// a FlatBuffer in some other buffer, such that you can later read it
  /// without first having to copy it into its own buffer.
  - size_t GetBufferMinAlignment() {
  + size_t GetBufferMinAlignment() const {
  Finished();
  return minalign_;
  }
  