sint32(value) {
        assert_1.assertInt32(value);
        // zigzag encode
        value = ((value << 1) ^ (value >> 31)) >>> 0;
        goog_varint_1.varint32write(value, this.buf);
        return this;
    }
Write a `sint32` value, a signed, zigzag-encoded 32-bit varint.