These wrappers are not natively understood by
ts2dart. Removing them will improve Dart2JS
compilation due to fewer megamorphic calls to List
functions.
It also makes Angular code more succinct and
improves type safety in Angular due to better type
inference of the Array component type.
This change exposed several bugs in Angular.
It is possible for a class defined first to be referencing a class defined later,
and as a result at the time of the definition it is not possible to access the later's
class reference. This allows to refer to the later defined class through
a closure.Closes #1891
