Bug 1070845 - [sharedtest] unit test refactoring for new version chai.assert api (rebased)

test_agent used very old version chai library version=0.5.3 in the current version=1.9.1 deepEqua
this.sinon.spy() in th line 518 -> TypeError: this is undefined
if var self = this;
and self.sinon.spy() in th line 518 -> TypeError: self.sinon is undefined