cps-ir: Handle factories and redirecting constructors with JS backend.

cps-ir: Handle factories and redirecting constructors with JS backend.

BUG=
R=karlklose@google.com

Committed: https://code.google.com/p/dart/source/detail?r=45128

[asgerf, 2015-04-13 14:27:34]

asgerf@google.com changed reviewers:
+ karlklose@google.com

[karlklose, 2015-04-14 07:22:45]

Does this handle redirecting factories like
  class C<T> implements D {}
  class D {
    factory D() = C<int>;
  }
?

If yes, please add a test, otherwise add a bailout in the codegen, if there is
none at the moment.

[asgerf, 2015-04-14 07:51:17]

Good point, and yes it handles it. Added a test case for it.

[karlklose, 2015-04-14 08:15:23]

LGTM.

[asgerf, 2015-04-14 08:25:33]

Committed patchset #5 (id:80001) manually as 45128 (presubmit successful).