`minify` cannot remove unused branch

Reproduction link:

https://esbuild.github.io/try/#YgAwLjI1LjIAeyAgICAKICAgIGZvcm1hdDogImVzbSIsCiAgICBtaW5pZnk6IHRydWUsCiAgICB0cmVlU2hha2luZzogdHJ1ZSwKfQBlAGVudHJ5LmpzAHZhciBmb28gPSAxOwpjb25zdCBmYWxzZV9kZWZhdWx0ID0gZmFsc2U7CgpleHBvcnQgZnVuY3Rpb24gZm4oKSB7CiAgaWYgKGZhbHNlX2RlZmF1bHQpIHsKICAgIGNvbnNvbGUud2FybigiSSBleHBlY3QgdGhpcyBzdHJpbmcgdG8gYmUgcmVtb3ZlZCIpCiAgfQoKICBjb25zb2xlLmxvZyhmb28pCn0

Expected output:

```js
var e=1;function o(){console.log(e)}export{o as fn};
```

Actual output:

```js
var o=1;const e=!1;function n(){e&&console.warn("I expect this string to be removed"),console.log(o)}export{n as fn};
```

For unknown reason, if I move `var foo = 1;` below `const false_default = false;`, I can get the expected output.

Use the linked esbuild playground reproduction with minification and tree shaking enabled, then compare the expected and actual bundles shown in the issue. There are no source files or tests named; done means the unused warning branch is removed while the shown exported function output remains correct.

Written by the indexing model from the issue text.