Consolidate the code that replaces a TypeParameter with its bound.

pkg/analyzer/lib/src/generated/element_resolver.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.src.generated.element_resolver;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
@@ skipping 2407 matching lines @@
         element = _lookUpMethod(null, enclosingType, identifier.name);
       }
     }
     return element;
   }
 
   /**
    * If the given [type] is a type parameter, resolve it to the type that should
    * be used when looking up members. Otherwise, return the original type.
    */
-  DartType _resolveTypeParameter(DartType type) {
-    if (type is TypeParameterType) {
-      DartType bound = type.element.bound;
-      if (bound == null) {
-        return _resolver.typeProvider.objectType;
-      }
-      return bound;
-    }
-    return type;
-  }
+  DartType _resolveTypeParameter(DartType type) =>
+      type?.resolveToBound(_resolver.typeProvider.objectType);
 
   /**
    * Return `true` if we should report an error as a result of looking up a
    * [member] in the given [type] and not finding any member.
    */
   bool _shouldReportMissingMember(DartType type, Element member) {
-    if (member != null || type == null || type.isDynamic || type.isBottom) {
-      return false;
-    }
-    return true;
+    return member == null && type != null && !type.isDynamic && !type.isBottom;
   }
 
   /**
    * Checks whether the given [expression] is a reference to a class. If it is
    * then the element representing the class is returned, otherwise `null` is
    * returned.
    */
   static ClassElementImpl getTypeReference(Expression expression) {
     if (expression is Identifier) {
       Element staticElement = expression.staticElement;
@@ skipping 136 matching lines @@
 
   @override
   Element get staticElement => null;
 
   @override
   accept(AstVisitor visitor) => null;
 
   @override
   void visitChildren(AstVisitor visitor) {}
 }