Fix crash with generalized function types in type tests.

pkg/front_end/lib/src/fasta/kernel/body_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.body_builder;
 
 import '../fasta_codes.dart'
     show FastaMessage, codeExpectedButGot, codeExpectedFunctionBody;
 
 import '../parser/parser.dart' show FormalParameterType, MemberKind, optional;
@@ skipping 1459 matching lines @@
         pop();
         warning("Type variables can only be used in instance methods.",
             beginToken.charOffset);
         push(const DynamicType());
       }
     }
   }
 
   @override
   void handleFunctionType(Token functionToken, Token endToken) {
+    debugEvent("FunctionType");
     FormalParameters formals = pop();
     ignore(Unhandled.TypeVariables);
     DartType returnType = pop();
     push(formals.toFunctionType(returnType));
   }
 
   @override
   void handleVoidKeyword(Token token) {
     debugEvent("VoidKeyword");
     push(const VoidType());
@@ skipping 93 matching lines @@
             type: type,
             initializer: name.initializer,
             isFinal: isFinal,
             isConst: isConst);
       } else {
         addCompileTimeError(offsetForToken(name.token),
             "'${name.name}' isn't a field in this class.");
       }
     }
     variable ??= astFactory.variableDeclaration(
-        name.name, name.token, functionNestingLevel,
+        name?.name, name?.token, functionNestingLevel,
         type: type,
-        initializer: name.initializer,
+        initializer: name?.initializer,
         isFinal: isFinal,
         isConst: isConst);
     push(variable);
   }
 
   @override
   void endOptionalFormalParameters(
       int count, Token beginToken, Token endToken) {
     debugEvent("OptionalFormalParameters");
     FormalParameterType kind = optional("{", beginToken)
@@ skipping 44 matching lines @@
     OptionalFormals optional;
     if (count > 0 && peek() is OptionalFormals) {
       optional = pop();
       count--;
     }
     FormalParameters formals = new FormalParameters(
         popList(count) ?? <VariableDeclaration>[],
         optional,
         beginToken.charOffset);
     push(formals);
-    if (inCatchClause || functionNestingLevel != 0) {
+    if ((inCatchClause || functionNestingLevel != 0) &&
+        kind != MemberKind.GeneralizedFunctionType) {
       enterLocalScope(formals.computeFormalParameterScope(
           scope, member ?? classBuilder ?? library));
     }
   }
 
   @override
   void beginCatchClause(Token token) {
     debugEvent("beginCatchClause");
     inCatchClause = true;
   }
@@ skipping 1493 matching lines @@
     if (starToken == null) {
       return AsyncMarker.Async;
     } else {
       assert(identical(starToken.stringValue, "*"));
       return AsyncMarker.AsyncStar;
     }
   } else {
     return internalError("Unknown async modifier: $asyncToken");
   }
 }