sinonjs: Update from 1.17.3 to 1.17.7
Upstream Sinon.JS no longer supports the pre-2.x v1.17 branch
anymore but there have been a few post-2.0 releases to address
bugs in v1.17 that we can still benefit from.
https://github.com/sinonjs/sinon/blob/v1.17.7/Changelog.txt
Notable changes include:
* Fix Blob feature test to support running tests on Safari 9.
* Avoid calls to object-local 'hasOwnProperty'.
* Improve error messages and stricter signature/type checks so
that debugging code is easier when things go wrong.
* Fix various gaps in the XHR mock.
* Misc fixes for Node.js support.
Also remove outdated comment about ie-hacks from Sinon 1.15.
Change-Id: I66d1b461465b92798ad7eb2efcf4df2731cc78a4