Diagnose missing @MirrorsUsed.

dart/sdk/lib/_internal/compiler/implementation/warnings.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.
 
 part of dart2js;
 
 const DONT_KNOW_HOW_TO_FIX = "";
 
 /**
  * The messages in this file should meet the following guide lines:
@@ skipping 1061 matching lines @@
 
   static const MessageKind DEFERRED_LIBRARY_NAME_MISMATCH =
       const MessageKind(
           "Error: Library name mismatch '#{expectedName}' != '#{actualName}'.");
 
   static const MessageKind ILLEGAL_STATIC = const MessageKind(
       "Error: Modifier static is only allowed on functions declared in "
       "a class.");
 
   static const MessageKind STATIC_FUNCTION_BLOAT = const MessageKind(
-      "Hint: Using '#{class}.#{name}' may result in larger output.");
+      "Hint: Using '#{class}.#{name}' may lead to unnecessarily large generated"
+      " code.",

[sigurdm, 2013/12/03 08:09:52]

It seems the tradition is to put the space on the previous line:
      "Hint: Using '#{class}.#{name}' may lead to unnecessarily large "
      "generated code."
6 occurrences in this file.

[ahe, 2013/12/03 15:39:07]

Done.

+      howToFix:
+          "Try adding '@MirrorsUsed(...)' as described at"
+          " https://goo.gl/Akrrog.");

[sigurdm, 2013/12/03 08:09:52]

The page referred to starts off a bit cryptic.
I cannot really parse: "EXPERIMENTAL API: Description of how "dart:mirrors" is
used."
It is not immediately clear what "non-normative" means.
Also the example is wrong. 'Mirrors' should be 'MirrorSystem'.

[ahe, 2013/12/03 15:39:07]

Done, except for the "non-normative" part. Not sure what to do about that.

Kathy: please take a look at my changes to mirrors.dart, and let me know if you
have any ideas.

 
-  static const MessageKind NON_CONST_BLOAT = const MessageKind('''
-Hint: Using "new #{name}' may result in larger output.
-Use 'const #{name}' if possible.''');
+  static const MessageKind NON_CONST_BLOAT = const MessageKind(
+      "Hint:Using 'new #{name}' may lead to unnecessarily large generated"

[Kathy Walrath, 2013/12/02 16:28:34]

Add a space after "Hint:"

[ahe, 2013/12/03 15:39:07]

Done.

+      " code.",
+      howToFix:
+          "Try using 'const #{name}' or adding '@MirrorsUsed(...)' as described"
+          " at https://goo.gl/Akrrog.");
 
   static const MessageKind STRING_EXPECTED = const MessageKind(
       "Error: Expected a 'String', but got an instance of '#{type}'.");
 
   static const MessageKind PRIVATE_IDENTIFIER = const MessageKind(
       "Error: '#{value}' is not a valid Symbol name because it starts with "
       "'_'.");
 
   static const MessageKind PRIVATE_NAMED_PARAMETER = const MessageKind(
       "Error: Named optional parameter can't have a library private name.",
@@ skipping 227 matching lines @@
       examples: const [
           "main();"]);
 
   static const MessageKind MIRROR_BLOAT = const MessageKind(
       "Hint: #{count} methods retained for use by dart:mirrors out of #{total}"
       " total methods (#{percentage}%).");
 
   static const MessageKind MIRROR_IMPORT = const MessageKind(
       "Info: Import of 'dart:mirrors'.");
 
+  static const MessageKind MIRROR_IMPORT_NO_USAGE = const MessageKind(
+      "Info: This import is not annotated with @MirrorsUsed, which may lead to"
+      " unnecessarily large generated code.",
+      howToFix:
+          "Try adding '@MirrorsUsed(...)' as described at"
+          " https://goo.gl/Akrrog.");
+
   static const MessageKind WRONG_ARGUMENT_FOR_JS_INTERCEPTOR_CONSTANT =
       const MessageKind(
       "Error: Argument for 'JS_INTERCEPTOR_CONSTANT' must be a type constant.");
 
   static const MessageKind EXPECTED_IDENTIFIER_NOT_RESERVED_WORD =
       const MessageKind(
           "Error: '#{keyword}' is a reserved word and can't be used here.",
           howToFix: "Try using a different name.",
           examples: const ["do() {} main() {}"]);
 
@@ skipping 235 matching lines @@
 
 class CompileTimeConstantError extends Diagnostic {
   CompileTimeConstantError(MessageKind kind, Map arguments, bool terse)
     : super(kind, arguments, terse);
 }
 
 class CompilationError extends Diagnostic {
   CompilationError(MessageKind kind, Map arguments, bool terse)
     : super(kind, arguments, terse);
 }