Clean up duplicate type inference code for fetching parameter types.

pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart

Index: pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart
diff --git a/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart b/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart
index f314593ffe0cf628cd99e72f580c003a4a8ed659..c93784cc1e00c975354bc4abf8b57d04e43f1959 100644
--- a/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart
+++ b/pkg/front_end/lib/src/fasta/type_inference/type_inference_engine.dart
@@ -266,18 +266,6 @@ abstract class TypeInferenceEngineImpl extends TypeInferenceEngine {
   /// a previous call to [createTopLevelTypeInferrer].
   TypeInferrerImpl getMemberTypeInferrer(KernelMember member);
 
-  DartType getNamedParameterType(FunctionType functionType, String name) {
-    return functionType.getNamedParameter(name) ?? const DynamicType();
-  }
-
-  DartType getPositionalParameterType(FunctionType functionType, int i) {
-    if (i < functionType.positionalParameters.length) {
-      return functionType.positionalParameters[i];
-    } else {
-      return const DynamicType();
-    }
-  }
-
   /// Performs type inference on the given [accessorNode].
   void inferAccessor(AccessorNode accessorNode) {
     assert(accessorNode.state == InferenceState.NotInferredYet);