Checks that setScriptSource works for editing the top-most stack frame
Paused at (before live edit):
function testExpression(a, b) {
  #debugger;
  return a + b;

Paused at (after live edit):
function testExpression(a, b) {
  #return a * b;
}

Result:
{
    description : 15
    type : number
    value : 15
}