CL: https://chromium-review.googlesource.com/c/418778/

The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra.git/+/9437e263aea4b8b7d335791bf4dc2dd4ec4acf56

commit 9437e263aea4b8b7d335791bf4dc2dd4ec4acf56
Author: Sergiy Byelozyorov <sergiyb@chromium.org>
Date: Fri Dec 09 14:38:33 2016

Use float64 instead of int64 for seconds_since_epoch fields

According to the spec, seconds_since_epoch should be float:
https://www.chromium.org/developers/the-json-test-results-format.

BUG= 672836 

Change-Id: Ie2ebf9d84ab8ce78ff92b3c48bd576f09e911ce6
Reviewed-on: https://chromium-review.googlesource.com/418778
Reviewed-by: Andrii Shyshkalov <tandrii@chromium.org>
Commit-Queue: Sergiy Byelozyorov <sergiyb@chromium.org>

[modify] https://crrev.com/9437e263aea4b8b7d335791bf4dc2dd4ec4acf56/go/src/infra/appengine/test-results/frontend/testdata/full_results_0.json
[modify] https://crrev.com/9437e263aea4b8b7d335791bf4dc2dd4ec4acf56/go/src/infra/appengine/test-results/frontend/upload.go
[modify] https://crrev.com/9437e263aea4b8b7d335791bf4dc2dd4ec4acf56/go/src/infra/appengine/test-results/frontend/upload_test.go
[modify] https://crrev.com/9437e263aea4b8b7d335791bf4dc2dd4ec4acf56/go/src/infra/appengine/test-results/model/aggregate_result.go
[modify] https://crrev.com/9437e263aea4b8b7d335791bf4dc2dd4ec4acf56/go/src/infra/appengine/test-results/model/aggregate_result_test.go
[modify] https://crrev.com/9437e263aea4b8b7d335791bf4dc2dd4ec4acf56/go/src/infra/appengine/test-results/model/end_to_end_test.go
[modify] https://crrev.com/9437e263aea4b8b7d335791bf4dc2dd4ec4acf56/go/src/infra/appengine/test-results/model/full_result.go
[modify] https://crrev.com/9437e263aea4b8b7d335791bf4dc2dd4ec4acf56/go/src/infra/appengine/test-results/model/full_result_test.go
[modify] https://crrev.com/9437e263aea4b8b7d335791bf4dc2dd4ec4acf56/go/src/infra/appengine/test-results/model/testdata/full_results.jsonp

Deployed this to prod.

 Issue 672830  has been merged into this issue.