dart2js cps: Do not propagate InvokeMethodDirectly receiver.

dart2js cps: Do not propagate InvokeMethodDirectly receiver.

The target function might not exist before the class has been
instantiated for the first time, so the receiver must be evaluated
before the callee expression.

BUG=
R=kmillikin@google.com

Committed: https://github.com/dart-lang/sdk/commit/d730063475ee11d9ee8ff43f20f9053b6d5646e2

[asgerf, 2015-11-09 12:51:33]

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

[Kevin Millikin (Google), 2015-11-09 13:07:14]

LGTM.  Instead of this:

      E.C.prototype.get$positional.call(E.D$());
      E.C.prototype.get$named.call(E.D$());

we now get this:

      var v0 = E.D$();
      E.C.prototype.get$positional.call(v0);
      v0 = E.D$();
      E.C.prototype.get$named.call(v0);

[asgerf, 2015-11-09 14:51:00]

Committed patchset #2 (id:20001) manually as
d730063475ee11d9ee8ff43f20f9053b6d5646e2 (presubmit successful).