Fails on x86

[marefr]

Following https://github.com/grafana/grafana/issues/26389

Here's two test cases that fails on x86: https://play.golang.org/p/_CjXY3ONfxs

First one returns the following error on x86 (same details in referenced issue):

month out of bounds 1455570369 at character 8 starting with "2"
  day 1455570368 out of bounds for month 1455570369 at character 11 starting with "1"
  hours out of bounds 1455570374 at character 14 starting with "7"
  minutes out of bounds 1455570367 at character 17 starting with "0"
  seconds out of bounds 1455570367 at character 20 starting with "0"'

Second one returns the following error on x86 (same details in referenced issue):

month out of bounds 1455570369 at character 8 starting with "2"
  day 1455570370 out of bounds for month 1455570369 at character 11 starting with "3"
  hours out of bounds 1455570375 at character 14 starting with "8"
  minutes out of bounds 1455570367 at character 17 starting with "0"
  seconds out of bounds 1455570367 at character 20 starting with "0"

Thanks