Add support for accessing field formal parameters in the initializer list of constructors

pkg/analyzer/lib/src/dart/constant/evaluation.dart

Index: pkg/analyzer/lib/src/dart/constant/evaluation.dart
diff --git a/pkg/analyzer/lib/src/dart/constant/evaluation.dart b/pkg/analyzer/lib/src/dart/constant/evaluation.dart
index aff65bcdc1a9bf23ce1afb8add0d71814a728437..ffd2cc86f7d19ec1122414157d14408f9402f758 100644
--- a/pkg/analyzer/lib/src/dart/constant/evaluation.dart
+++ b/pkg/analyzer/lib/src/dart/constant/evaluation.dart
@@ -654,10 +654,9 @@ class ConstantEvaluationEngine {
             }
             fieldMap[fieldName] = argumentValue;
           }
-        } else {
-          String name = baseParameter.name;
-          parameterMap[name] = argumentValue;
         }
+        String name = baseParameter.name;
+        parameterMap[name] = argumentValue;
       }
     }
     ConstantVisitor initializerVisitor = new ConstantVisitor(