Processed metrics metadata 

This is what happens when API format is original in the browser: 
http://demo2.piwik.org/index.php?module=API&method=VisitsSummary.get&idSite=1&period=day&date=yesterday&format=original&token_auth=637769d1f85f8bde0001943db1491a02

And this when `format=html`:

http://demo2.piwik.org/index.php?module=API&method=VisitsSummary.get&idSite=1&period=day&date=yesterday&format=html&token_auth=637769d1f85f8bde0001943db1491a02

The latter is just the unescaped text of the former. There is no reason to use format=original in an HTTP request.

If you format values all the time, this change will not fix the sumRowArray bug.