Various issues with duplicated names.

pkg/front_end/lib/src/fasta/kernel/kernel_library_builder.dart

 // Copyright (c) 2016, 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 fasta.kernel_library_builder;
 
 import 'package:front_end/src/scanner/token.dart' show Token;
 
 import 'package:kernel/ast.dart';
 
@@ skipping 527 matching lines @@
           name,
           typeVariables,
           formals,
           kind,
           this,
           charOffset,
           charOpenParenOffset,
           charEndOffset,
           nativeMethodName);
     }
+    checkTypeVariables(typeVariables, procedure);
     addBuilder(name, procedure, charOffset);
     if (nativeMethodName != null) {
       addNativeMethod(procedure);
     }
   }
 
   void addFactoryMethod(
       List<MetadataBuilder> metadata,
       int modifiers,
       ConstructorReferenceBuilder constructorNameReference,
@@ skipping 47 matching lines @@
 
   void addFunctionTypeAlias(
       List<MetadataBuilder> metadata,
       KernelTypeBuilder returnType,
       String name,
       List<TypeVariableBuilder> typeVariables,
       List<FormalParameterBuilder> formals,
       int charOffset) {
     FunctionTypeAliasBuilder typedef = new KernelFunctionTypeAliasBuilder(
         metadata, returnType, name, typeVariables, formals, this, charOffset);
+    checkTypeVariables(typeVariables, typedef);
     // Nested declaration began in `OutlineBuilder.beginFunctionTypeAlias`.
     endNestedDeclaration().resolveTypes(typeVariables, this);
     addBuilder(name, typedef, charOffset);
   }
 
   KernelFunctionTypeBuilder addFunctionType(
       KernelTypeBuilder returnType,
       List<TypeVariableBuilder> typeVariables,
       List<FormalParameterBuilder> formals,
       int charOffset) {
-    return addType(new KernelFunctionTypeBuilder(
-        charOffset, fileUri, returnType, typeVariables, formals));
+    var builder = new KernelFunctionTypeBuilder(
+        charOffset, fileUri, returnType, typeVariables, formals);
+    checkTypeVariables(typeVariables, builder);
+    return addType(builder);
   }
 
   KernelFormalParameterBuilder addFormalParameter(
       List<MetadataBuilder> metadata,
       int modifiers,
       KernelTypeBuilder type,
       String name,
       bool hasThis,
       int charOffset) {
     return new KernelFormalParameterBuilder(
@@ skipping 208 matching lines @@
           mixinApplicationClasses.putIfAbsent(name, () => builder);
       if (existing != builder) {
         part.scope.local.remove(name);
       }
     });
     super.includePart(part);
     nativeMethods.addAll(part.nativeMethods);
     boundlessTypeVariables.addAll(part.boundlessTypeVariables);
   }
 }