[Minor] Expressions with trailing . (dot) evaluate differently in standard / ng-csp mode

[kosprov]

I run into an ng-grid bug that makes the component behave differently in standard / ng-csp mode.

The problem lies in the fact that an expression with a trailing . evaluates to nothing when ng-csp is off and to the last property when ng-csp is on ({{foo.bar.}} is effectively the same as {{foo.bar}}).

Of course, trailing dots is something that can easily be considered illegal (throw an Error in both cases maybe).

Check out these plunkers: ng-csp off / ng-csp on.