Use "this" in static methods

[joeyparrish]

To solve #2528, we need to upgrade the compiler. A side-benefit of the upgrade is that we will finally be able to use this in static methods. The use of this in static methods has long been part of ES6 classes, but the compiler version we used did not support it.

We should clean up our many, many self-aliases in static methods. For example, in lib/util/string_utils.js, we currently have this:

  static fromBytesAutoDetect(data) {
    const StringUtils = shaka.util.StringUtils;
    // ...
      return StringUtils.fromUTF8(uint8);

The alias would be removed and the call site would use this instead:

  static fromBytesAutoDetect(data) {
    // ...
      return this.fromUTF8(uint8);

[avelad]

Since our plan is to migrate to TypeScript, @joeyparrish, are you okay if we close this issue?

[joeyparrish]

Yes, fine with me.