John "codefu" McDole ff983d3598
feat: start using the content aware hash for downloading artifacts (#172552)
reland of https://github.com/flutter/flutter/pull/171927
towards https://github.com/flutter/flutter/issues/171790

Use the content aware hash when downloading engine artifacts. These are
currently produced when changes to DEPs, engine/, or the release file
are changed in a not-seen-before way.

We can eventually remove engine.version being tracked in release
branches as an optimization.

FLUTTER_PREBUILT_ENGINE_VERSION will stay for overriding the
engine.version for testing. Though Cocoon does not need to actually set
it for framework only PRs anymore.

fxies post submit tests for content_hash download:
SHARD=framework_tests SUBSHARD=misc dart --enable-asserts
dev/bots/test.dart
SHARD=tool_host_cross_arch_tests dart --enable-asserts
dev/bots/test.dart

```
  ╔═╡ERROR https://github.com/flutter/flutter/pull/1╞════════════════════════════════════════════════════════════════════
  ║ Expected "Flutter Engine Version: 45b085ab2118f30441ae6e2daab4b8eb3e4a063c", but found "Flutter Engine Version: 407c051ec9".
  ╚═══════════════════════════════════════════════════════════════════════════════
```

```
  Expected: contains '45b085ab2118f30441ae6e2daab4b8eb3e4a063c'
     Which: does not contain '45b085ab2118f30441ae6e2daab4b8eb3e4a063c'
```
2025-07-22 17:35:26 +00:00
..
2025-06-02 18:35:14 +00:00
2025-06-02 18:35:14 +00:00
2025-06-02 18:35:14 +00:00
2024-12-18 20:18:06 +00:00
2025-07-11 15:27:12 +00:00

Flutter SDK dependency versions

The files in this directory specifies pinned versions of various dependencies of the flutter SDK.

The bin/internal/engine.version file controls where to find compiled artifacts of the engine. These artifacts are compiled in the Merge Queue for every commit in the flutter repository.

The bin/internal/flutter_packages.version file specifies the version of the flutter/packages repository to be used for testing. The flutter/packages repository isn't an upstream dependency of flutter/flutter; it is only used as part of the test suite for verification, and the pinned version here makes sure that tests are deterministic at each flutter/flutter commit.