Allow modification of ListTile's horizontalTitleGap, minVerticalPadding, minLeadingWidth

This relands #68587

initialize the flutter root as early as possible. This allows all interfaces to be normally injected into commands, even if those objects might read from the flutter root.

Change forwarding command to pass through all args, even -h - this allows flutter to support all of the pub flags without needing to declare them.

This reverts commit 4bd89b39.

This reverts commit 422a97d1 due to https://github.com/flutter/flutter/issues/69863

This reverts commit e375651c.

Co-authored-by: altherat <contact@altherat.com>

This reverts commit ada6b7e5.

For the ease of code reviews, this only includes minimal code from
MetricPoint, GoogleBenchmarksParser, and their unit tests.

See go/flutter-metrics-center-migration for the overall plan.