Rewrite ImplicitConstructorBuilder to use only element model.

pkg/analyzer/lib/src/generated/testing/element_factory.dart

Index: pkg/analyzer/lib/src/generated/testing/element_factory.dart
diff --git a/pkg/analyzer/lib/src/generated/testing/element_factory.dart b/pkg/analyzer/lib/src/generated/testing/element_factory.dart
index cc8c62287dde546b7ca8111c347581db9ac79545..9fab12ff89342406125ec4b9db39a4f18c0efd55 100644
--- a/pkg/analyzer/lib/src/generated/testing/element_factory.dart
+++ b/pkg/analyzer/lib/src/generated/testing/element_factory.dart
@@ -70,6 +70,18 @@ class ElementFactory {
           [List<String> parameterNames]) =>
       classElement(typeName, objectType, parameterNames);
 
+  static ClassElementImpl classTypeAlias2(String typeName,
+          [List<String> parameterNames]) =>
+      classTypeAlias(typeName, objectType, parameterNames);
+
+  static classTypeAlias(String typeName, InterfaceType superclassType,
+      [List<String> parameterNames]) {
+    ClassElementImpl element =
+        classElement(typeName, superclassType, parameterNames);
+    element.typedef = true;
+    return element;
+  }
+
   static CompilationUnitElementImpl compilationUnit(String fileName) {
     Source source = new NonExistingSource(fileName, UriKind.FILE_URI);
     CompilationUnitElementImpl unit = new CompilationUnitElementImpl(fileName);
@@ -202,9 +214,8 @@ class ElementFactory {
       setter.setter = true;
       setter.synthetic = true;
       setter.variable = field;
-      setter.parameters = <ParameterElement>[
-        requiredParameter2("_$name", type)
-      ];
+      setter.parameters =
+          <ParameterElement>[requiredParameter2("_$name", type)];
       setter.returnType = VoidTypeImpl.instance;
       setter.type = new FunctionTypeImpl.con1(setter);
       field.setter = setter;
@@ -507,9 +518,8 @@ class ElementFactory {
       setter.static = true;
       setter.synthetic = true;
       setter.variable = variable;
-      setter.parameters = <ParameterElement>[
-        requiredParameter2("_$name", type)
-      ];
+      setter.parameters =
+          <ParameterElement>[requiredParameter2("_$name", type)];
       setter.returnType = VoidTypeImpl.instance;
       setter.type = new FunctionTypeImpl.con1(setter);
       variable.setter = setter;