Add --dart-define option support to build aar command (#71829)

packages/flutter_tools/lib/src/commands/build_aar.dart

@@ -40,6 +40,7 @@ class BuildAarCommand extends BuildSubCommand {
     usesPubOption();
     addSplitDebugInfoOption();
     addDartObfuscationOption();
+    usesDartDefineOption();
     usesTrackWidgetCreation(verboseHelp: false);
     addNullSafetyModeOptions(hide: !verboseHelp);
     addEnableExperimentation(hide: !verboseHelp);

packages/flutter_tools/test/commands.shard/permeable/build_aar_test.dart

@@ -176,6 +176,7 @@ void main() {
           '--split-debug-info',
           '/project-name/v1.2.3/',
           '--obfuscate',
+          '--dart-define=foo=bar'
         ],
       );
 
@@ -196,6 +197,7 @@ void main() {
       expect(buildInfo.flavor, 'free');
       expect(buildInfo.splitDebugInfoPath, '/project-name/v1.2.3/');
       expect(buildInfo.dartObfuscation, isTrue);
+      expect(buildInfo.dartDefines.contains('foo=bar'), isTrue);
     }, overrides: <Type, Generator>{
       AndroidBuilder: () => mockAndroidBuilder,
     });