Query reponse time and Query time histogram not graphing

In our setup the Query Response Time and Query Time Histogram are not graphing.

It took me a whle to pinpoint the problem, but I'm happy to say I finally found it:
In the ss_get_mysql_stats.php script the following query gets executed:
SELECT `count`, total * 1000000 AS total FROM INFORMATION_SCHEMA.QUERY_RESPONSE_TIME WHERE `time` <> 'TOO LONG'

This results in a thirteen row result, which then gets assigned to the $status['Query_time_count_%2d'] and $status['Query_time_total_%2d'] variables. This will assign Query_time_count_00 till Query_time_count_12 and Query_time_total_00 till Query_time_total_12 with a value.

However at line 757 the script will check if the value is set. As Query_time_count_13 and Query_time_total_13 will not be set and the returned value at line 760 is -1.
Since templates are only allowed to contain values ranging from 0 to 18446744073709551615 and not -1 the whole measurement will be deferred.

The fix could be any of the following three options:
1. Change templates to allow -1 value
2. Change templates to only contain 13 data points instead of 14
3. Change the query in the ss_get_mysql_stats.php script

We fixed our instance by patching the ss_get_mysql_stats.php script and remove line 480 containing the where. I've attached our patch for completeness and hopefully it can help others as well.