Incorrect location info in SAXParser and RewritingStream

[RReverser]

When concatenating consequent character tokens, streaming variants of the parser don't correctly merge location information.

I found related issue #153 where endOffset was fixed for SAXParser, but endLine and endCol are still invalid and correspond to the first token.

Test for the RewritingStream (not for SAXParser as initially I thought the problem is specific to the rewriter) as an example of the issue:

exports['RewritingStream - Should return location for entire text span'] = createRewriterTest({
    src: 'te\n st',
    expected: '',
    assignTokenHandlers: rewriter => {
        rewriter.on('text', token => {
            assert.deepStrictEqual(token, {
                text: 'te\n st',
                sourceCodeLocation: {
                    startLine: 1,
                    startCol: 1,
                    startOffset: 0,
                    endLine: 2, // returns 1 instead
                    endCol: 4, // returns 3 instead
                    endOffset: 6
                }
            });
        });
    }
});