code: @Override @DefinedBy(Api.COMPILER_TREE)
      public TypeMirror getOriginalType(javax.lang.model.type.ErrorType errorType) {
          if (errorType instanceof com.sun.tools.javac.code.Type.ErrorType) {
              return ((com.sun.tools.javac.code.Type.ErrorType)errorType).getOriginalType();
          }
  
          return com.sun.tools.javac.code.Type.noType;
      }
docs: Returns the original type from the ErrorType object.
  @param errorType The errorType for which we want to get the original type.
  @return TypeMirror corresponding to the original type, replaced by the ErrorType.
  noType (type.tag == NONE) is returned if there is no original type.