[JS] Generated closure leads to a runtime exception

Haxe 4.3.6.
This example is a bit nonsensical, real-world code makes sense, I just pared it down into a small example where the issue can be reproduced.

```haxe filename=src/Test.hx
package;

using Lambda;

class Test {
static final list = [ 1, 2, 3 ];

static function main() {
trace([ 5, 6, 4 ].exists(list.contains));
}
}
```

```hxml filename=build.hxml
-D no-inline

-cp src
-main Test

-js bin/test.js

--cmd node bin/test.js
```

The following code compiles (when using `-D no-inline`), becoming:
```js
...
console.log("src/Test.hx:9:",Lambda.exists([5,6,4],($_=Test.list,$bind($_,$_.contains))));
...
```

The `$_` refers to a (JS) array, which doesn't have the `contains` function (JS uses `includes` for the same thing), therefore `$_.contains` is null and the generated binding (`f`) is faulty. The code fails at runtime with this error:
_TypeError: f is not a function_