Reverts "Manual roll of Dart. (#54983)"

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Reverts: #54983

Initiated by: zanderso

Reason for reverting: The roll to the framework is failing on the version of the synthetic _macros package: https://logs.chromium.org/logs/flutter/buildbucket/cr-buildbucket/8737528015332264641/+/u/flutter_config_--clear-features/stdout

Original PR Author: a-siva

Reviewed By: {zanderso}

This change reverts the following previous change:
https://dart.googlesource.com/sdk.git/+log/1a6246225b75..0f783bdb7a4d

Merging Version 3.6.0-217.0.dev

The change https://dart-review.googlesource.com/c/sdk/+/382385 moved some package locations and these had to be adjusted in the Flutter DEPS file.

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