Frog: compiler crashes on undeclared variable

[rakudrama]

Compiling this program crashes Frog.
check1b.dart:
class Bogon {
  var x;
  Bogon(this.x);
}

class Foo1 {
  choop(x){}
}

main() {
  test1();
}

test1() {
  var b1 = new Bogon(6);
  var b2 = new Bogon(17);

  try {
    var b3 = b1.choop(b2);
    print(b4); /// <<<---------------------------------
  } catch (var e) {
    print('Exception $e');
  }
}

$ ~/dart-all/dart/frog/frogsh --enable_type_checks --out=t1.js check1b.dart

node.js:134
        throw e; // process.nextTick error, or 'error' event on first tick
        ^
TypeError: Cannot read property 'members' of null
    at BareValue._hasOverriddenNoSuchMethod (/usr/local/google/home/sra/dart-all/dart/frog/frogsh:19427:51)
    at BareValue.resolveMember (/usr/local/google/home/sra/dart-all/dart/frog/frogsh:19448:90)
    at BareValue.get (/usr/local/google/home/sra/dart-all/dart/frog/frogsh:19370:21)
    at MethodGenerator.visitVarExpression (/usr/local/google/home/sra/dart-all/dart/frog/frogsh:12117:42)
    at VarExpression.visit (/usr/local/google/home/sra/dart-all/dart/frog/frogsh:18095:18)
    at MethodGenerator.visitValue (/usr/local/google/home/sra/dart-all/dart/frog/frogsh:11258:20)
    at MethodGenerator._makeArgs (/usr/local/google/home/sra/dart-all/dart/frog/frogsh:11219:19)
    at MethodGenerator.visitCallExpression (/usr/local/google/home/sra/dart-all/dart/frog/frogsh:11726:51)
    at CallExpression.visit (/usr/local/google/home/sra/dart-all/dart/frog/frogsh:17939:18)
    at MethodGenerator.visitValue (/usr/local/google/home/sra/dart-all/dart/frog/frogsh:11258:20)
$

[jmesserly]

fixed this in another change. :)

/Users/jmesserly/scratch/test.dart:20:11: error: can not resolve "b4" on "test"
    print(b4); /// <<<---------------------------------
          ^^

(full disclosure: there's also a goofy error now about 'can not resolve "noSuchMethod" on "test" ... but that's a different issue)

---

Added Fixed label.