Use entities in TypeVariableResolutionAnalysis and TypeVariableCodegenAnalysis

pkg/compiler/lib/src/common_elements.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.
 
 // TODO(sigmund): rename and move to common/elements.dart
 library dart2js.type_system;
 
 import 'common/names.dart' show Uris;
 import 'elements/types.dart';
 import 'elements/entities.dart';
@@ skipping 267 matching lines @@
   DartType get dynamicType;
 
   /// Returns the 'raw type' of [cls]. That is, the instantiation of [cls]
   /// where all types arguments are `dynamic`.
   InterfaceType getRawType(ClassEntity cls);
 
   /// Returns the 'this type' of [cls]. That is, the instantiation of [cls]
   /// where the type arguments are the type variables of [cls].
   InterfaceType getThisType(ClassEntity cls);
 
+  /// The upper bound on the [typeVariable]. If not explicitly declared, this is
+  /// `Object`.
+  DartType getTypeVariableBound(TypeVariableEntity typeVariable);
+
   /// Returns `true` if [a] is a subtype of [b].
   bool isSubtype(DartType a, DartType b);
 
   /// Returns the type if [function].
   FunctionType getFunctionType(FunctionEntity function);
 
   /// Returns the [CallStructure] corresponding to calling [entity] with all
   /// arguments, both required and optional.
   CallStructure getCallStructure(FunctionEntity entity);
 
@@ skipping 270 matching lines @@
   }
 
   @override
   InterfaceType streamType([DartType elementType]) {
     if (elementType == null) {
       return getRawType(streamClass);
     }
     return createInterfaceType(streamClass, [elementType]);
   }
 }