tests: add test for bad template %include and __base__
It doesn't seem like we had any tests for `%include non-existent` and
`__base__ = non-existent`. The latter raises an error while the former
ignores the include. We should probably also make the former an error.
Differential Revision: https://phab.mercurial-scm.org/D8798
{
// Enforcing
"eqeqeq" : true, // true: Require triple equals (===) for comparison
"forin" : true, // true: Require filtering for..in loops with obj.hasOwnProperty()
"freeze" : true, // true: prohibits overwriting prototypes of native objects such as Array, Date etc.
"nonbsp" : true, // true: Prohibit "non-breaking whitespace" characters.
"undef" : true, // true: Require all non-global variables to be declared (prevents global leaks)
// Environments
"browser" : true // Web Browser (window, document, etc)
}