[conductor] Remove CiYaml model (#120458)

* [conductor] Remove CiYaml model

* Remove package:yaml

* Update pubspec checksum

dev/conductor/core/lib/src/repository.dart

@@ -10,7 +10,6 @@ import 'package:file/file.dart';
 import 'package:meta/meta.dart';
 import 'package:platform/platform.dart';
 import 'package:process/process.dart';
-import 'package:yaml/yaml.dart';
 
 import './git.dart';
 import './globals.dart';
@@ -599,12 +598,6 @@ class FrameworkRepository extends Repository {
   static const String defaultUpstream = 'git@github.com:flutter/flutter.git';
   static const String defaultBranch = 'master';
 
-  Future<CiYaml> get ciYaml async {
-    final CiYaml ciYaml =
-        CiYaml((await checkoutDirectory).childFile('.ci.yaml'));
-    return ciYaml;
-  }
-
   Future<String> get cacheDirectory async {
     return fileSystem.path.join(
       (await checkoutDirectory).path,
@@ -857,11 +850,6 @@ class EngineRepository extends Repository {
 
   final Checkouts checkouts;
 
-  Future<CiYaml> get ciYaml async {
-    final CiYaml ciYaml = CiYaml((await checkoutDirectory).childFile('.ci.yaml'));
-    return ciYaml;
-  }
-
   static const String defaultUpstream = 'git@github.com:flutter/engine.git';
   static const String defaultBranch = 'main';
 
@@ -930,26 +918,3 @@ class Checkouts {
   final ProcessManager processManager;
   final Stdio stdio;
 }
-
-class CiYaml {
-  CiYaml(this.file) {
-    if (!file.existsSync()) {
-      throw ConductorException('Could not find the .ci.yaml file at ${file.path}');
-    }
-  }
-
-  /// Underlying [File] that this object wraps.
-  final File file;
-
-  /// Returns the raw string contents of this file.
-  ///
-  /// This is not cached as the contents can be written to while the conductor
-  /// is running.
-  String get stringContents => file.readAsStringSync();
-
-  /// Returns the parsed contents of the file as a [YamlMap].
-  ///
-  /// This is not cached as the contents can be written to while the conductor
-  /// is running.
-  YamlMap get contents => loadYaml(stringContents) as YamlMap;
-}

dev/conductor/core/pubspec.yaml

@@ -15,7 +15,6 @@ dependencies:
   path: 1.8.3
   process: 4.2.4
   protobuf: 2.1.0
-  yaml: 3.1.1
 
   async: 2.10.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   clock: 1.1.1 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
@@ -65,4 +64,4 @@ dev_dependencies:
   web_socket_channel: 2.3.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
   webkit_inspection_protocol: 1.2.0 # THIS LINE IS AUTOGENERATED - TO UPDATE USE "flutter update-packages --force-upgrade"
 
-# PUBSPEC CHECKSUM: f01f
+# PUBSPEC CHECKSUM: 721e

dev/conductor/core/test/repository_test.dart

@@ -393,15 +393,6 @@ vars = {
       expect(didUpdate, false);
     });
 
-    test('CiYaml(file) will throw if file does not exist', () {
-      final File file = fileSystem.file('/non/existent/file.txt');
-
-      expect(
-        () => CiYaml(file),
-        throwsExceptionWith('Could not find the .ci.yaml file at /non/existent/file.txt'),
-      );
-    });
-
     test('framework repo set as localUpstream ensures requiredLocalBranches exist locally', () async {
       const String commit = 'deadbeef';
       const String candidateBranch = 'flutter-1.2-candidate.3';