Normalize Compact and Expanded reporters

[natebosch]

Working towards #1311

The Compact and Expanded reporters have a lot of code in common,
along with many superficial, and a few not-superficial differences. Some
of the impactful differences look like they may be bugs. Make it easier
to understand both reporters and their differences by reducing the
superficial changes.

The JSON reporter shares less code with the others, but aim for a
consistent field ordering there as well.

• Avoid using Configuration.current from the compact reporter. This
  was never added in the expanded reporter to avoid a transitive import
  to dart:io. The pattern of being configured at construction is
  already baked in to the ReporterFactory typedef and is a more clear
  pattern than reading from a magic zone scoped variable. Add required
  constructor args for the compact reporter which match those in the
  expanded reporter. Remove the TODO.
• Use the same pattern for setting the color escape code fields. In the
  future we will likely want to migrate to package:io for these.
• Shuffle some fields so they are ordered consistently in both
  reporters.
• Add a default for _lastProgressPassed to avoid making it nullable.
• Add _printPath and _printPlatform fields in the compact reporter
  rather than read them lazily through the zone scoped configuration.
• Make the arguments required for the constructors instead of adding
  defaults which are never used.
• Use 2 slashs for comments.

[natebosch]

I did not (or at least not intentionally) change any behavior or fix any bugs here.

[grouma]

[nit] move this back if it wasn't touched

[natebosch]

I changed this because all 3 reporters have these same 3 fields directly before the constructor. If you look at a diff between them this minimizes the noise (although admittedly that is less useful in this case because this reporter is more different overall)