public Builder addExtensionRange(com.google.protobuf.DescriptorProtos.DescriptorProto.ExtensionRange value) {
        if (extensionRangeBuilder_ == null) {
          if (value == null) {
            throw new NullPointerException();
          }
          ensureExtensionRangeIsMutable();
          extensionRange_.add(value);
          onChanged();
        } else {
          extensionRangeBuilder_.addMessage(value);
        }
        return this;
      }