DartC does not allow '=>' on factory constructors.

[DartBot]

This issue was originally filed by ngeoffray@google.com

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Run the following code (tests/language/src/FactoryArrowTest.dart):

class A {
  A.foo() {}
  factory A() => new A.foo();
}

main() {
 Expect.isTrue(new A() is A);
}

Fails with:

     6: A.foo() {}
     7: factory A() => new A.foo();
                      ~~

tests/language/src/FactoryArrowTest.dart/FactoryArrowTest.dart:13:1: Unexpected token 'EOS'

[DartBot]

This comment was originally written by mmendez@google.com

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Set owner to fab...@google.com.
Added Accepted label.

[DartBot]

This comment was originally written by fab...@google.com

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Added Started label.

[DartBot]

This comment was originally written by fab...@google.com

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Added Fixed label.