…73114)"

This reverts commit eb786c8.

…lutter/flutter#173114)

…lutter/flutter#173114)

…lutter/flutter#173114)

…lutter/flutter#173114)

…lutter/flutter#173114)

…lutter/flutter#173114)

Roll Flutter from 871849e4b6bf to beda687d63f2 (34 revisions)

flutter/flutter@871849e...beda687

2025-08-04 [email protected] [Impeller] Improvements to the Vulkan pipeline cache data writer (flutter/flutter#173014)
2025-08-04 [email protected] [Impeller] Terminate the fence waiter but do not reset it during ContextVK shutdown (flutter/flutter#173085)
2025-08-04 [email protected] Add the 'windowing' feature flag and use to wrap an implementation for regular windows that always throws (flutter/flutter#172478)
2025-08-04 [email protected] licenses_cpp: reland switch 4 (flutter/flutter#173139)
2025-08-04 [email protected] Roll Skia from 763bba9c33fd to dce9550a1356 (1 revision) (flutter/flutter#173219)
2025-08-04 [email protected] Improve robustness of comment detection when using flutter analyze --suggestions (flutter/flutter#172977)
2025-08-04 [email protected] Make sure that a LicensePage doesn't crash in 0x0 environment (flutter/flutter#172610)
2025-08-04 [email protected] Roll Packages from f0645d8 to 1a72287 (4 revisions) (flutter/flutter#173215)
2025-08-04 [email protected] Roll Skia from edf0f8a5bba6 to 763bba9c33fd (1 revision) (flutter/flutter#173213)
2025-08-04 [email protected] [web] Add Intl.Locale to parse browser languages. (flutter/flutter#172964)
2025-08-04 [email protected] Roll Skia from 439f80973f4a to edf0f8a5bba6 (2 revisions) (flutter/flutter#173204)
2025-08-04 [email protected] Roll Skia from 9d30cc96a3b2 to 439f80973f4a (1 revision) (flutter/flutter#173201)
2025-08-04 [email protected] Roll Skia from 39c70f883c0e to 9d30cc96a3b2 (1 revision) (flutter/flutter#173197)
2025-08-04 [email protected] Roll Skia from 09667386bcba to 39c70f883c0e (1 revision) (flutter/flutter#173194)
2025-08-04 [email protected] fix: get content hash for master on local engine branches (third attempt)  (flutter/flutter#173169)
2025-08-03 [email protected] Roll Fuchsia Linux SDK from wZuA8Dqty4scQkZuV... to ufssK8EgJ_9RpLFgu... (flutter/flutter#173190)
2025-08-03 [email protected] Roll Skia from e056e47e118b to 09667386bcba (2 revisions) (flutter/flutter#173185)
2025-08-03 [email protected] fix: tag fuchsia package after uploading (flutter/flutter#173140)
2025-08-02 [email protected] Roll Skia from 7ef888e30a28 to e056e47e118b (1 revision) (flutter/flutter#173170)
2025-08-02 [email protected] Roll Fuchsia Linux SDK from yFLr81lLXmSX7n11D... to wZuA8Dqty4scQkZuV... (flutter/flutter#173166)
2025-08-02 [email protected] Roll Skia from af6d6eb383a6 to 7ef888e30a28 (1 revision) (flutter/flutter#173157)
2025-08-02 [email protected] Add `innerRadius` to `RadioThemeData` (flutter/flutter#173120)
2025-08-02 [email protected] Roll Skia from 81dd6aa516b0 to af6d6eb383a6 (2 revisions) (flutter/flutter#173144)
2025-08-01 98614782+auto-submit[bot]@users.noreply.github.com Reverts "fix: get content hash for master on local engine branches (#173114)" (flutter/flutter#173145)
2025-08-01 [email protected] Roll Dart SDK from 6e1bb159c860 to 3f1307d72d6f (2 revisions) (flutter/flutter#173136)
2025-08-01 [email protected] Roll Skia from 9e2c59634961 to 81dd6aa516b0 (1 revision) (flutter/flutter#173135)
2025-08-01 [email protected] Reformat text.dart's code snippets (flutter/flutter#172976)
2025-08-01 [email protected] experiment with docs properties (flutter/flutter#173124)
2025-08-01 [email protected] fix: get content hash for master on local engine branches (flutter/flutter#173114)
2025-08-01 [email protected] Make sure that a RawAutocomplete doesn't crash in 0x0 environment (flutter/flutter#172812)
2025-08-01 [email protected] Add skia_ports_fontmgr_android_parser_sources (flutter/flutter#172979)
2025-08-01 [email protected] Roll Skia from 49e39cd3cf18 to 9e2c59634961 (10 revisions) (flutter/flutter#173125)
2025-08-01 [email protected] fix: 🐛 Add equality and hashCode implementations to ResizeImage (flutter/flutter#172643)
2025-08-01 [email protected] Roll Fuchsia Linux SDK from xo_bqOoFuBKFmgKxn... to yFLr81lLXmSX7n11D... (flutter/flutter#173117)

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/flutter-packages
Please CC [email protected],[email protected] on the revert to ensure that a human
is aware of the problem.

To file a bug in Packages: https://github.com/flutter/flutter/issues/new/choose

To report a problem with the AutoRoller itself, please file a bug:
https://issues.skia.org/issues/new?component=1389291&template=1850622

...

…mpt) (flutter#173169)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#173114 (try 2)
re-land attempt for flutter#172792 (original)

The first commit in this PR is the previously LGTM'd changes for the
above; with tests.

The second commit is the critical change to make this work in post
submits (fixes flutter#173143). It turns out that while LUCI reports the GitHub
private branches; our recipes directly checkout the git sha. This
matters because the content scripts couldn't determine the branch name
and the rev-parse was just HEAD. This lead the scripts down the
merge-base logic, which returns the previous commit.

A test was added specifically for this.

Alternatively to this change, we could have checked for LUCI_CONTEXT
being present in the environment. This is checked by Flutter tools in
some cases, but not by any other scripts in `bin/internal`. The downside
to checking HEAD: if you have a local branch with engine changes and you
move back a revision - `dart`/`flutter` invocations will generate the
hash for your local changes and fail.

…3114)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#172792  with the following changes:

1. content_aware_hash.(ps1|sh) now consider multiple branches to choose
between HEAD and merge-base.
2. content_aware_hash_test.dart updated for these new requirements 
3. content_aware_hash_test.dart allows for forcing powershell on mac for
testing
4. updated docs/tool/Engine-artifacts.md documentation.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

…lutter#173114)" (flutter#173145)

<!-- start_original_pr_link -->
Reverts: flutter#173114
<!-- end_original_pr_link -->
<!-- start_initiating_author -->
Initiated by: jtmcdole
<!-- end_initiating_author -->
<!-- start_revert_reason -->
Reason for reverting: there is still another problem with the merge
queue causing the content hash to be different:

git revision: e13dd53
actual hash: 4b6f7b0f9849efaa59f515c8e95f3f27a6eb2ffb
hash in the queue? 9e5b2eef4ba79b15b4f80dbba812d199d262366f



<!-- end_revert_reason -->
<!-- start_original_pr_author -->
Original PR Author: jtmcdole
<!-- end_original_pr_author -->

<!-- start_reviewers -->
Reviewed By: {matanlurey, chingjun}
<!-- end_reviewers -->

<!-- start_revert_body -->
This change reverts the following previous change:
The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#172792  with the following changes:

1. content_aware_hash.(ps1|sh) now consider multiple branches to choose
between HEAD and merge-base.
2. content_aware_hash_test.dart updated for these new requirements 
3. content_aware_hash_test.dart allows for forcing powershell on mac for
testing
4. updated docs/tool/Engine-artifacts.md documentation.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

<!-- end_revert_body -->

Co-authored-by: auto-submit[bot] <[email protected]>

…mpt) (flutter#173169)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#173114 (try 2)
re-land attempt for flutter#172792 (original)

The first commit in this PR is the previously LGTM'd changes for the
above; with tests.

The second commit is the critical change to make this work in post
submits (fixes flutter#173143). It turns out that while LUCI reports the GitHub
private branches; our recipes directly checkout the git sha. This
matters because the content scripts couldn't determine the branch name
and the rev-parse was just HEAD. This lead the scripts down the
merge-base logic, which returns the previous commit.

A test was added specifically for this.

Alternatively to this change, we could have checked for LUCI_CONTEXT
being present in the environment. This is checked by Flutter tools in
some cases, but not by any other scripts in `bin/internal`. The downside
to checking HEAD: if you have a local branch with engine changes and you
move back a revision - `dart`/`flutter` invocations will generate the
hash for your local changes and fail.

…3114)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#172792  with the following changes:

1. content_aware_hash.(ps1|sh) now consider multiple branches to choose
between HEAD and merge-base.
2. content_aware_hash_test.dart updated for these new requirements 
3. content_aware_hash_test.dart allows for forcing powershell on mac for
testing
4. updated docs/tool/Engine-artifacts.md documentation.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

…lutter#173114)" (flutter#173145)

<!-- start_original_pr_link -->
Reverts: flutter#173114
<!-- end_original_pr_link -->
<!-- start_initiating_author -->
Initiated by: jtmcdole
<!-- end_initiating_author -->
<!-- start_revert_reason -->
Reason for reverting: there is still another problem with the merge
queue causing the content hash to be different:

git revision: e13dd53
actual hash: 4b6f7b0f9849efaa59f515c8e95f3f27a6eb2ffb
hash in the queue? 9e5b2eef4ba79b15b4f80dbba812d199d262366f



<!-- end_revert_reason -->
<!-- start_original_pr_author -->
Original PR Author: jtmcdole
<!-- end_original_pr_author -->

<!-- start_reviewers -->
Reviewed By: {matanlurey, chingjun}
<!-- end_reviewers -->

<!-- start_revert_body -->
This change reverts the following previous change:
The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#172792  with the following changes:

1. content_aware_hash.(ps1|sh) now consider multiple branches to choose
between HEAD and merge-base.
2. content_aware_hash_test.dart updated for these new requirements 
3. content_aware_hash_test.dart allows for forcing powershell on mac for
testing
4. updated docs/tool/Engine-artifacts.md documentation.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

<!-- end_revert_body -->

Co-authored-by: auto-submit[bot] <[email protected]>

…mpt) (flutter#173169)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#173114 (try 2)
re-land attempt for flutter#172792 (original)

The first commit in this PR is the previously LGTM'd changes for the
above; with tests.

The second commit is the critical change to make this work in post
submits (fixes flutter#173143). It turns out that while LUCI reports the GitHub
private branches; our recipes directly checkout the git sha. This
matters because the content scripts couldn't determine the branch name
and the rev-parse was just HEAD. This lead the scripts down the
merge-base logic, which returns the previous commit.

A test was added specifically for this.

Alternatively to this change, we could have checked for LUCI_CONTEXT
being present in the environment. This is checked by Flutter tools in
some cases, but not by any other scripts in `bin/internal`. The downside
to checking HEAD: if you have a local branch with engine changes and you
move back a revision - `dart`/`flutter` invocations will generate the
hash for your local changes and fail.

…3114)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#172792  with the following changes:

1. content_aware_hash.(ps1|sh) now consider multiple branches to choose
between HEAD and merge-base.
2. content_aware_hash_test.dart updated for these new requirements 
3. content_aware_hash_test.dart allows for forcing powershell on mac for
testing
4. updated docs/tool/Engine-artifacts.md documentation.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

…lutter#173114)" (flutter#173145)

<!-- start_original_pr_link -->
Reverts: flutter#173114
<!-- end_original_pr_link -->
<!-- start_initiating_author -->
Initiated by: jtmcdole
<!-- end_initiating_author -->
<!-- start_revert_reason -->
Reason for reverting: there is still another problem with the merge
queue causing the content hash to be different:

git revision: e13dd53
actual hash: 4b6f7b0f9849efaa59f515c8e95f3f27a6eb2ffb
hash in the queue? 9e5b2eef4ba79b15b4f80dbba812d199d262366f



<!-- end_revert_reason -->
<!-- start_original_pr_author -->
Original PR Author: jtmcdole
<!-- end_original_pr_author -->

<!-- start_reviewers -->
Reviewed By: {matanlurey, chingjun}
<!-- end_reviewers -->

<!-- start_revert_body -->
This change reverts the following previous change:
The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#172792  with the following changes:

1. content_aware_hash.(ps1|sh) now consider multiple branches to choose
between HEAD and merge-base.
2. content_aware_hash_test.dart updated for these new requirements 
3. content_aware_hash_test.dart allows for forcing powershell on mac for
testing
4. updated docs/tool/Engine-artifacts.md documentation.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

<!-- end_revert_body -->

Co-authored-by: auto-submit[bot] <[email protected]>

…mpt) (flutter#173169)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#173114 (try 2)
re-land attempt for flutter#172792 (original)

The first commit in this PR is the previously LGTM'd changes for the
above; with tests.

The second commit is the critical change to make this work in post
submits (fixes flutter#173143). It turns out that while LUCI reports the GitHub
private branches; our recipes directly checkout the git sha. This
matters because the content scripts couldn't determine the branch name
and the rev-parse was just HEAD. This lead the scripts down the
merge-base logic, which returns the previous commit.

A test was added specifically for this.

Alternatively to this change, we could have checked for LUCI_CONTEXT
being present in the environment. This is checked by Flutter tools in
some cases, but not by any other scripts in `bin/internal`. The downside
to checking HEAD: if you have a local branch with engine changes and you
move back a revision - `dart`/`flutter` invocations will generate the
hash for your local changes and fail.

…3114)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#172792  with the following changes:

1. content_aware_hash.(ps1|sh) now consider multiple branches to choose
between HEAD and merge-base.
2. content_aware_hash_test.dart updated for these new requirements 
3. content_aware_hash_test.dart allows for forcing powershell on mac for
testing
4. updated docs/tool/Engine-artifacts.md documentation.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

…lutter#173114)" (flutter#173145)

<!-- start_original_pr_link -->
Reverts: flutter#173114
<!-- end_original_pr_link -->
<!-- start_initiating_author -->
Initiated by: jtmcdole
<!-- end_initiating_author -->
<!-- start_revert_reason -->
Reason for reverting: there is still another problem with the merge
queue causing the content hash to be different:

git revision: e13dd53
actual hash: 4b6f7b0f9849efaa59f515c8e95f3f27a6eb2ffb
hash in the queue? 9e5b2eef4ba79b15b4f80dbba812d199d262366f



<!-- end_revert_reason -->
<!-- start_original_pr_author -->
Original PR Author: jtmcdole
<!-- end_original_pr_author -->

<!-- start_reviewers -->
Reviewed By: {matanlurey, chingjun}
<!-- end_reviewers -->

<!-- start_revert_body -->
This change reverts the following previous change:
The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#172792  with the following changes:

1. content_aware_hash.(ps1|sh) now consider multiple branches to choose
between HEAD and merge-base.
2. content_aware_hash_test.dart updated for these new requirements 
3. content_aware_hash_test.dart allows for forcing powershell on mac for
testing
4. updated docs/tool/Engine-artifacts.md documentation.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

<!-- end_revert_body -->

Co-authored-by: auto-submit[bot] <[email protected]>

…mpt) (flutter#173169)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#173114 (try 2)
re-land attempt for flutter#172792 (original)

The first commit in this PR is the previously LGTM'd changes for the
above; with tests.

The second commit is the critical change to make this work in post
submits (fixes flutter#173143). It turns out that while LUCI reports the GitHub
private branches; our recipes directly checkout the git sha. This
matters because the content scripts couldn't determine the branch name
and the rev-parse was just HEAD. This lead the scripts down the
merge-base logic, which returns the previous commit.

A test was added specifically for this.

Alternatively to this change, we could have checked for LUCI_CONTEXT
being present in the environment. This is checked by Flutter tools in
some cases, but not by any other scripts in `bin/internal`. The downside
to checking HEAD: if you have a local branch with engine changes and you
move back a revision - `dart`/`flutter` invocations will generate the
hash for your local changes and fail.

…lutter/flutter#173114)

…3114)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#172792  with the following changes:

1. content_aware_hash.(ps1|sh) now consider multiple branches to choose
between HEAD and merge-base.
2. content_aware_hash_test.dart updated for these new requirements 
3. content_aware_hash_test.dart allows for forcing powershell on mac for
testing
4. updated docs/tool/Engine-artifacts.md documentation.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

…lutter#173114)" (flutter#173145)

<!-- start_original_pr_link -->
Reverts: flutter#173114
<!-- end_original_pr_link -->
<!-- start_initiating_author -->
Initiated by: jtmcdole
<!-- end_initiating_author -->
<!-- start_revert_reason -->
Reason for reverting: there is still another problem with the merge
queue causing the content hash to be different:

git revision: e13dd53
actual hash: 4b6f7b0f9849efaa59f515c8e95f3f27a6eb2ffb
hash in the queue? 9e5b2eef4ba79b15b4f80dbba812d199d262366f



<!-- end_revert_reason -->
<!-- start_original_pr_author -->
Original PR Author: jtmcdole
<!-- end_original_pr_author -->

<!-- start_reviewers -->
Reviewed By: {matanlurey, chingjun}
<!-- end_reviewers -->

<!-- start_revert_body -->
This change reverts the following previous change:
The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#172792  with the following changes:

1. content_aware_hash.(ps1|sh) now consider multiple branches to choose
between HEAD and merge-base.
2. content_aware_hash_test.dart updated for these new requirements 
3. content_aware_hash_test.dart allows for forcing powershell on mac for
testing
4. updated docs/tool/Engine-artifacts.md documentation.

## Pre-launch Checklist

- [x] I read the [Contributor Guide] and followed the process outlined
there for submitting PRs.
- [x] I read the [Tree Hygiene] wiki page, which explains my
responsibilities.
- [x] I read and followed the [Flutter Style Guide], including [Features
we expect every widget to implement].
- [x] I signed the [CLA].
- [x] I listed at least one issue that this PR fixes in the description
above.
- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
[test-exempt].
- [ ] I followed the [breaking change policy] and added [Data Driven
Fixes] where supported.
- [x] All existing and new tests are passing.

<!-- end_revert_body -->

Co-authored-by: auto-submit[bot] <[email protected]>

…mpt) (flutter#173169)

The content hash doesn't exist for local engine changes, except for on
CI. If we detect we're on a branch with committed or uncommitted changes
to engine files; use "master".

towards flutter#171790

re-land attempt for flutter#173114 (try 2)
re-land attempt for flutter#172792 (original)

The first commit in this PR is the previously LGTM'd changes for the
above; with tests.

The second commit is the critical change to make this work in post
submits (fixes flutter#173143). It turns out that while LUCI reports the GitHub
private branches; our recipes directly checkout the git sha. This
matters because the content scripts couldn't determine the branch name
and the rev-parse was just HEAD. This lead the scripts down the
merge-base logic, which returns the previous commit.

A test was added specifically for this.

Alternatively to this change, we could have checked for LUCI_CONTEXT
being present in the environment. This is checked by Flutter tools in
some cases, but not by any other scripts in `bin/internal`. The downside
to checking HEAD: if you have a local branch with engine changes and you
move back a revision - `dart`/`flutter` invocations will generate the
hash for your local changes and fail.