add missing trailing commas (in dev/) (#40704)

diff --git a/dev/automated_tests/flutter_test/package_assets_test.dart b/dev/automated_tests/flutter_test/package_assets_test.dart
index 8e1c574..187d13c 100644
--- a/dev/automated_tests/flutter_test/package_assets_test.dart
+++ b/dev/automated_tests/flutter_test/package_assets_test.dart
@@ -13,7 +13,7 @@
         width: 54,
         height: 54,
         fit: BoxFit.none,
-        package: 'flutter_automated_tests'
+        package: 'flutter_automated_tests',
       ),
     );
   });
diff --git a/dev/automated_tests/flutter_test/print_user_created_ancestor_no_flag_test.dart b/dev/automated_tests/flutter_test/print_user_created_ancestor_no_flag_test.dart
index 74ea6fd..23bb39b 100644
--- a/dev/automated_tests/flutter_test/print_user_created_ancestor_no_flag_test.dart
+++ b/dev/automated_tests/flutter_test/print_user_created_ancestor_no_flag_test.dart
@@ -12,7 +12,7 @@
       CustomScrollView(
         slivers: <Widget>[
           SliverToBoxAdapter(child: Container()),
-        ]
+        ],
       )
     );
   });
diff --git a/dev/automated_tests/flutter_test/print_user_created_ancestor_test.dart b/dev/automated_tests/flutter_test/print_user_created_ancestor_test.dart
index 74ea6fd..23bb39b 100644
--- a/dev/automated_tests/flutter_test/print_user_created_ancestor_test.dart
+++ b/dev/automated_tests/flutter_test/print_user_created_ancestor_test.dart
@@ -12,7 +12,7 @@
       CustomScrollView(
         slivers: <Widget>[
           SliverToBoxAdapter(child: Container()),
-        ]
+        ],
       )
     );
   });
diff --git a/dev/bots/test.dart b/dev/bots/test.dart
index 15d0ff2..1d2cdc8 100644
--- a/dev/bots/test.dart
+++ b/dev/bots/test.dart
@@ -228,7 +228,7 @@
       environment: <String, String>{
         'FLUTTER_ROOT': flutterRoot,
         'SUBSHARD': subshards[i],
-      }
+      },
     );
   }
 }
@@ -299,7 +299,7 @@
     expectNonZeroExit: expectNonZeroExit,
     environment: <String, String>{
       'FLUTTER_WEB': 'true',
-    }
+    },
   );
   print('Done.');
 }
@@ -554,7 +554,7 @@
       args,
       workingDirectory: workingDirectory,
       environment: pubEnvironment,
-      beforeExit: formatter.finish
+      beforeExit: formatter.finish,
     );
     await _processTestOutput(formatter, testOutput, tableData);
   } else {
@@ -563,7 +563,7 @@
       args,
       workingDirectory:workingDirectory,
       environment:pubEnvironment,
-      removeLine: (String line) => line.contains('[INFO]')
+      removeLine: (String line) => line.contains('[INFO]'),
     );
   }
 }
diff --git a/dev/devicelab/bin/tasks/gradle_plugin_fat_apk_test.dart b/dev/devicelab/bin/tasks/gradle_plugin_fat_apk_test.dart
index cc3f149..5788e96 100644
--- a/dev/devicelab/bin/tasks/gradle_plugin_fat_apk_test.dart
+++ b/dev/devicelab/bin/tasks/gradle_plugin_fat_apk_test.dart
@@ -130,7 +130,7 @@
         // for arm and arm64.
         final List<String> targetPlatforms = <String>[
           'android-arm',
-          'android-arm64'
+          'android-arm64',
         ];
         for (final String targetPlatform in targetPlatforms) {
           final String androidArmSnapshotPath = path.join(
diff --git a/dev/devicelab/bin/tasks/module_test_ios.dart b/dev/devicelab/bin/tasks/module_test_ios.dart
index 081e98f..5ffd3e0 100644
--- a/dev/devicelab/bin/tasks/module_test_ios.dart
+++ b/dev/devicelab/bin/tasks/module_test_ios.dart
@@ -263,7 +263,7 @@
           ],
           environment: <String, String> {
             'FLUTTER_ANALYTICS_LOG_FILE': objectiveCAnalyticsOutputFile.path,
-          }
+          },
         );
       });
 
@@ -306,7 +306,7 @@
             'CONFIGURATION_BUILD_DIR=${objectiveCBuildDirectory.path}',
             'COMPILER_INDEX_STORE_ENABLE=NO',
           ],
-          canFail: true
+          canFail: true,
         );
       });
 
@@ -346,7 +346,7 @@
           ],
           environment: <String, String> {
             'FLUTTER_ANALYTICS_LOG_FILE': swiftAnalyticsOutputFile.path,
-          }
+          },
         );
       });
 
@@ -383,7 +383,7 @@
     app.path,
     'Frameworks',
     'App.framework',
-    'App'
+    'App',
   );
 
   final String symbolTable = await eval(
@@ -402,7 +402,7 @@
     app.path,
     'Frameworks',
     'App.framework',
-    'App'
+    'App',
   );
 
   final String symbolTable = await eval(
diff --git a/dev/devicelab/bin/tasks/system_debug_ios.dart b/dev/devicelab/bin/tasks/system_debug_ios.dart
index aabaca3..ae9f920 100644
--- a/dev/devicelab/bin/tasks/system_debug_ios.dart
+++ b/dev/devicelab/bin/tasks/system_debug_ios.dart
@@ -44,7 +44,7 @@
     '--verbose-system-logs',
     '-d',
     deviceId,
-    'lib/empty.dart'
+    'lib/empty.dart',
   ]);
 
   expect(!output.contains(expectedWarning));
@@ -84,9 +84,9 @@
     '--verbose-system-logs',
     '-d',
     deviceId,
-    'lib/empty.dart'
+    'lib/empty.dart',
   ], environment: <String, String>{
-    'FLUTTER_TOOLS_DEBUG_WITHOUT_CHECKED_MODE': 'true'
+    'FLUTTER_TOOLS_DEBUG_WITHOUT_CHECKED_MODE': 'true',
   });
   expect(output.contains(expectedWarning));
 }
\ No newline at end of file
diff --git a/dev/devicelab/lib/tasks/perf_tests.dart b/dev/devicelab/lib/tasks/perf_tests.dart
index bae1243..88c6f81 100644
--- a/dev/devicelab/lib/tasks/perf_tests.dart
+++ b/dev/devicelab/lib/tasks/perf_tests.dart
@@ -689,7 +689,7 @@
       _device = null;
 
       final Map<String, dynamic> reportedDuration = <String, dynamic>{
-        'duration': duration
+        'duration': duration,
       };
       _device = null;
 
diff --git a/dev/devicelab/lib/tasks/plugin_tests.dart b/dev/devicelab/lib/tasks/plugin_tests.dart
index c706ada..bf6c64e 100644
--- a/dev/devicelab/lib/tasks/plugin_tests.dart
+++ b/dev/devicelab/lib/tasks/plugin_tests.dart
@@ -105,7 +105,7 @@
           '--org',
           'io.flutter.devicelab',
           ...options,
-          name
+          name,
         ],
       );
     });
diff --git a/dev/integration_tests/android_splash_screens/splash_screen_kitchen_sink/test_driver/main.dart b/dev/integration_tests/android_splash_screens/splash_screen_kitchen_sink/test_driver/main.dart
index b04fbf6..d9cc6a7 100644
--- a/dev/integration_tests/android_splash_screens/splash_screen_kitchen_sink/test_driver/main.dart
+++ b/dev/integration_tests/android_splash_screens/splash_screen_kitchen_sink/test_driver/main.dart
@@ -38,7 +38,7 @@
   // Channel used for Android to send Flutter changes to the splash display.
   const BasicMessageChannel<String> testChannel = BasicMessageChannel<String>(
       'testChannel',
-      StringCodec()
+      StringCodec(),
   );
 
   // Every splash display change message that we receive from Android is either
diff --git a/dev/tools/vitool/bin/main.dart b/dev/tools/vitool/bin/main.dart
index d2f0dc8..2af6622 100644
--- a/dev/tools/vitool/bin/main.dart
+++ b/dev/tools/vitool/bin/main.dart
@@ -18,32 +18,32 @@
       'help',
       abbr: 'h',
       negatable: false,
-      help: 'Display the tool\'s usage instructions and quit.'
+      help: 'Display the tool\'s usage instructions and quit.',
   );
 
   parser.addOption(
       'output',
       abbr: 'o',
-      help: 'Target path to write the generated Dart file to.'
+      help: 'Target path to write the generated Dart file to.',
   );
 
   parser.addOption(
       'asset-name',
       abbr: 'n',
-      help: 'Name to be used for the generated constant.'
+      help: 'Name to be used for the generated constant.',
   );
 
   parser.addOption(
       'part-of',
       abbr: 'p',
-      help: 'Library name to add a dart \'part of\' clause for.'
+      help: 'Library name to add a dart \'part of\' clause for.',
   );
 
   parser.addOption(
       'header',
       abbr: 'd',
       help: 'File whose contents are to be prepended to the beginning of '
-            'the generated Dart file; this can be used for a license comment.'
+            'the generated Dart file; this can be used for a license comment.',
   );
 
   parser.addFlag(
@@ -51,7 +51,7 @@
       abbr: 'c',
       defaultsTo: true,
       help: 'Whether to include the following comment after the header:\n'
-            '$kCodegenComment'
+            '$kCodegenComment',
   );
 
   final ArgResults argResults = parser.parse(args);
diff --git a/dev/tools/vitool/test/vitool_test.dart b/dev/tools/vitool/test/vitool_test.dart
index cd65312..7f7217a 100644
--- a/dev/tools/vitool/test/vitool_test.dart
+++ b/dev/tools/vitool/test/vitool_test.dart
@@ -22,19 +22,19 @@
 
   test('parsePoints', () {
     expect(parsePoints('1.0, 2.0'),
-        const <Point<double>>[Point<double>(1.0, 2.0)]
+        const <Point<double>>[Point<double>(1.0, 2.0)],
     );
     expect(parsePoints('12.0, 34.0 5.0, 6.6'),
         const <Point<double>>[
           Point<double>(12.0, 34.0),
           Point<double>(5.0, 6.6),
-        ]
+        ],
     );
     expect(parsePoints('12.0 34.0 5.0 6.6'),
         const <Point<double>>[
           Point<double>(12.0, 34.0),
           Point<double>(5.0, 6.6),
-        ]
+        ],
     );
   });
 
@@ -47,19 +47,19 @@
     test('illegal SVGs', () {
       expect(
         () { interpretSvg(testAsset('illegal_svg_multiple_roots.svg')); },
-        throwsA(anything)
+        throwsA(anything),
       );
     });
 
     test('SVG size', () {
       expect(
           interpretSvg(testAsset('empty_svg_1_48x48.svg')).size,
-          const Point<double>(48.0, 48.0)
+          const Point<double>(48.0, 48.0),
       );
 
       expect(
           interpretSvg(testAsset('empty_svg_2_100x50.svg')).size,
-          const Point<double>(100.0, 50.0)
+          const Point<double>(100.0, 50.0),
       );
     });
 
@@ -83,7 +83,7 @@
     test('SVG illegal path', () {
       expect(
         () { interpretSvg(testAsset('illegal_path.svg')); },
-        throwsA(anything)
+        throwsA(anything),
       );
     });
 
@@ -148,14 +148,14 @@
               SvgPathCommand('Z', <Point<double>>[]),
             ]),
             margin: precisionErrorTolerance,
-        )
+        ),
       ]);
     });
 
     test('SVG illegal transform', () {
       expect(
         () { interpretSvg(testAsset('illegal_transform.svg')); },
-        throwsA(anything)
+        throwsA(anything),
       );
     });
 
@@ -235,8 +235,8 @@
                   <Point<double>>[Point<double>(10.0, 10.0)],
                 ]),
               ],
-              opacities: <double>[1.0]
-          ))
+              opacities: <double>[1.0],
+          )),
       );
     });
 
@@ -265,10 +265,10 @@
               <PathCommandAnimation>[
                 PathCommandAnimation('M', <List<Point<double>>>[
                   <Point<double>>[Point<double>(0.0, 0.0)],
-                ])
+                ]),
               ],
-              opacities: <double>[1.0]
-          ))
+              opacities: <double>[1.0],
+          )),
       );
 
       expect(PathAnimation.fromFrameData(frameData, 1),
@@ -278,8 +278,8 @@
                   <Point<double>>[Point<double>(5.0, 6.0)],
                 ])
               ],
-              opacities: <double>[1.0]
-          ))
+              opacities: <double>[1.0],
+          )),
       );
     });
 
@@ -291,7 +291,7 @@
             SvgPath(
               'path_1',
               <SvgPathCommand>[
-                SvgPathCommand('M', <Point<double>>[Point<double>(0.0, 0.0)])
+                SvgPathCommand('M', <Point<double>>[Point<double>(0.0, 0.0)]),
               ],
               opacity: 0.5,
             ),
@@ -303,7 +303,7 @@
             SvgPath(
               'path_1',
               <SvgPathCommand>[
-                SvgPathCommand('M', <Point<double>>[Point<double>(10.0, 10.0)])
+                SvgPathCommand('M', <Point<double>>[Point<double>(10.0, 10.0)]),
               ],
             ),
           ],
@@ -319,8 +319,8 @@
                   ],
                 ]),
               ],
-              opacities: <double>[0.5, 1.0]
-          ))
+              opacities: <double>[0.5, 1.0],
+          )),
       );
     });
   });
@@ -352,10 +352,10 @@
               <PathCommandAnimation>[
                 PathCommandAnimation('M', <List<Point<double>>>[
                   <Point<double>>[Point<double>(0.0, 0.0)],
-                ])
+                ]),
               ],
-              opacities: <double>[1.0]
-          ))
+              opacities: <double>[1.0],
+          )),
       );
 
       expect(animation.paths[1],
@@ -363,10 +363,10 @@
               <PathCommandAnimation>[
                 PathCommandAnimation('M', <List<Point<double>>>[
                   <Point<double>>[Point<double>(5.0, 6.0)],
-                ])
+                ]),
               ],
-              opacities: <double>[1.0]
-          ))
+              opacities: <double>[1.0],
+          )),
       );
 
       expect(animation.size, const Point<double>(10.0, 10.0));
@@ -391,7 +391,7 @@
           '            const Offset(1.0, 2.0),\n'
           '            const Offset(3.0, 4.0),\n'
           '          ],\n'
-          '        ),\n'
+          '        ),\n',
 
       );
     });
@@ -413,7 +413,7 @@
           '            const Offset(1.0, 2.0),\n'
           '            const Offset(3.0, 4.0),\n'
           '          ],\n'
-          '        ),\n'
+          '        ),\n',
 
       );
     });
@@ -451,7 +451,7 @@
           '            const Offset(40.0, 40.0),\n'
           '            const Offset(40.0, 40.0),\n'
           '          ],\n'
-          '        ),\n'
+          '        ),\n',
 
       );
     });
@@ -464,7 +464,7 @@
 
       expect(command.toDart(),
           '        const _PathClose(\n'
-          '        ),\n'
+          '        ),\n',
 
       );
     });
@@ -477,7 +477,7 @@
 
       expect(
         () { command.toDart(); },
-        throwsA(anything)
+        throwsA(anything),
       );
     });
 
@@ -497,7 +497,7 @@
               ],
             ]),
           ],
-          opacities: <double>[0.5, 1.0]
+          opacities: <double>[0.5, 1.0],
       );
 
       expect(pathAnimation.toDart(),
@@ -520,7 +520,7 @@
           '          ],\n'
           '        ),\n'
           '      ],\n'
-          '    ),\n'
+          '    ),\n',
       );
     });
 
@@ -543,7 +543,7 @@
                     ],
                   ]),
                 ],
-                opacities: <double>[0.5, 1.0]
+                opacities: <double>[0.5, 1.0],
             ),
 
             PathAnimation(
@@ -555,7 +555,7 @@
                     ],
                   ]),
                 ],
-                opacities: <double>[0.5, 1.0]
+                opacities: <double>[0.5, 1.0],
             ),
           ]);
 
@@ -598,7 +598,7 @@
           '      ],\n'
           '    ),\n'
           '  ],\n'
-          ');'
+          ');',
       );
     });
   });