Accessing fields of dynamically resolved fields fails

[iposva-google]

The code below fails to compile with this error message:
'Bug.dart': Error: line 12 pos 11: Unresolved identifier 'b'
    print(b.a);
          ^
Instead it should properly compile and lookup the b property dynamically on this in a similar fashion to the way it looks up 'a' in the foo method.

class A extends C {
  var a;
  var b;
}

class C {
  foo() {
    print(a);
    return a;
  }
  bar() {
    print(b.a);
    return b.a;
  }
}

main() {
  var a = new A();
  a.a = 1;
  a.b = a;
  Expect.equals(1, a.foo());
  Expect.equals(1, a.bar());
}

[iposva-google]

Removed Priority-Medium label.
Added Priority-High label.

[iposva-google]

Marked this as blocking #475.

[DartBot]

This comment was originally written by @mhausner

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Fixed at r4550.

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Added Fixed label.