Some notes on this function: first off, JavaScript uses camelcasing, rather than the C style underscore naming, so don't use tag_name, etc. but tagName, etc. Also, look at the code style in the rest of the code to see how indent, spacing, parens, etc. are done: you need a space between the ) and { after the function name/parameter string, and spaces in front of the return statement.

It's also better not to try to white-space align the code. In this case we can rewrite the function to this, instead:

```
function isActiveContent(tagName, attrName) {
  if (attrName === "href") {
    return ["a", "link"].indexOf(tagName) > -1;
  }
  if (attrName === "src") {
    return ["script", "iframe"].indexOf(tagName) > -1;
  }
  return false;
}
```
We can exploit the indexOf property for arrays to do multiple-string matching, and a code path shortcut based on the attribute name.