Revert "Enable syntax-only support for generic functions by default."

pkg/compiler/lib/src/diagnostics/messages.dart

 // Copyright (c) 2011, 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.
 
 /**
  * The messages in this file should meet the following guide lines:
  *
  * 1. The message should be a complete sentence starting with an uppercase
  * letter, and ending with a period.
  *
@@ skipping 1203 matching lines @@
   m(T t) => const C<T>();
 }
 
 void main() => new C().m(null);
 """
           ]),
 
       MessageKind.TYPE_VARIABLE_FROM_METHOD_NOT_REIFIED: const MessageTemplate(
           MessageKind.TYPE_VARIABLE_FROM_METHOD_NOT_REIFIED,
           "Method type variables do not have a runtime value.",
+          options: const ["--generic-method-syntax"],
           howToFix: "Try using the upper bound of the type variable, "
               "or refactor the code to avoid needing this runtime value.",
           examples: const [
             """
 // Method type variables are not reified, so they cannot be returned.
 Type f<T>() => T;
 
 main() => f<int>();
 """,
             """
 // Method type variables are not reified, so they cannot be tested dynamically.
 bool f<T>(Object o) => o is T;
 
 main() => f<int>(42);
 """
           ]),
 
       MessageKind.TYPE_VARIABLE_FROM_METHOD_CONSIDERED_DYNAMIC:
       const MessageTemplate(
           MessageKind.TYPE_VARIABLE_FROM_METHOD_CONSIDERED_DYNAMIC,
           "Method type variables are treated as `dynamic` in `as` expressions.",
+          options: const ["--generic-method-syntax"],
           howToFix: "Try using the upper bound of the type variable, or check "
               "that the blind success of the test does not introduce bugs.",
           examples: const [
             """
 // Method type variables are not reified, so they cannot be tested dynamically.
 bool f<T>(Object o) => o as T;
 
 main() => f<int>(42);
 """
           ]),
@@ skipping 2572 matching lines @@
   static String convertToString(value) {
     if (value is ErrorToken) {
       // Shouldn't happen.
       return value.assertionMessage;
     } else if (value is Token) {
       value = value.value;
     }
     return '$value';
   }
 }