Revert "Update to the latest shelf and shelf_static"
Revert "Update to the latest shelf and shelf_static"

This reverts commit 1f9fcfd9990ce11704d8a615559c1670d74c506f.

Reason for revert: Breaks internal tests.

Original change's description:
> Update to the latest shelf and shelf_static
>
> Change-Id: I6b8e4d39de4147d8b27132877ca2fc6a93a96761
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/198882
> Reviewed-by: Kevin Moore <1d6e7d10d051cf619c5282da3c28fd8d3e0a65a4@google.com>
> Commit-Queue: Kevin Moore <1d6e7d10d051cf619c5282da3c28fd8d3e0a65a4@google.com>
> Auto-Submit: Nate Bosch <dc212c74d8afde9c690fdd09e74d3e5c5d5a3de0@google.com>

# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I2aa86c3df68518e1b64598abe5dfa8f053632b0d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/199120
Reviewed-by: Nate Bosch <dc212c74d8afde9c690fdd09e74d3e5c5d5a3de0@google.com>
Reviewed-by: Kevin Moore <1d6e7d10d051cf619c5282da3c28fd8d3e0a65a4@google.com>
Commit-Queue: Nate Bosch <dc212c74d8afde9c690fdd09e74d3e5c5d5a3de0@google.com>

dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk