Fix for #2715

This fixes the part of #2715 where

```coffeescript
test = (obj) -> obj.value
trans = (obj) -> obj

test trans
  value: 'test'
```

ends up compiling to

```javascript
(function() {
  var test, trans;

  test = function(obj) {
    return obj.value;
  };

  trans = function(obj) {
    return obj;
  };

  test(trans)({
    value: 'test'
  });

}).call(this);
```

rather than

```javascript
(function() {
  var test, trans;

  test = function(obj) {
    return obj.value;
  };

  trans = function(obj) {
    return obj;
  };

  test(trans({
    value: 'test'
  }));

}).call(this);
```

At the same time,

```coffeescript
pass = ->
  true

result = if pass 1
  one: 1
eq result.one, 1
```

still compiles to

```javascript
(function() {
  var pass, result;

  pass = function() {
    return true;
  };

  result = pass(1) ? {
    one: 1
  } : void 0;

  eq(result.one, 1);

}).call(this);
```

The main heuristic used here is that the object in the second CoffeeScript snippet follows a statement (`if` in this case, though `for`, `while`, etc. are also considered) where it is more likely to serve as a return value.