functions re-declared in the global scope don't warn

[lukeapage]

In this code:

function a() { // wrong? not unused
}
function a() { // wrong? no error
}
a();

function b() {
  function a() { // wrong ? not unused
  }
  function a() { // a is already defined
  }
  a();
}
b();

the source looks like it doesn't warn about the re-definition deliberatly.. why? should it?

[lukeapage]

duplicate of #1304