test(ngAria): test that aria-hidden/disabled are always "true" or "false"
test(ngAria): test that aria-hidden/disabled are always "true" or "false"

Previously, when using ngAria with the ng-hide directive,
and the value passed to ng-hide was not boolean,
the aria-hidden attribute was set to this non-boolean value.

Closes #11865
Closes #11998

ggershoni/angular.js,ggershoni/angular.js,ggershoni/angular.js,ggershoni/angular.js