Most JavaScript packages wrap their code in IIFEs, which is good.

Pipeline used to concatenate JS only with a newline. That can break those IIFES
though:

    (function() {
      // package A
    }()) // No semicolon! Most people put one here, but unfortunately not all!
    (function() {
      // package B
    }());

The above is equivalent to:

    (function() {
      // package A
    }())(function() {
      // package B
    }());

Suddenly we have a function call!

With this commit, JS is concatenated with a newline followed by a semicolon,
which fixes the above issue:

    (function() {
      // package A
    }()) // No semicolon! Most people put one here, but unfortunately not all!
    ;(function() {
      // package B
    }());

There is no need to worry about superfluos semicolons, such as:

    (function() {
      // package A
    }());
    ;;(function() {
      // package B
    }());

That is still valid JavaScript and the extra semicolons will be removed by the
minifier.