Retain elements a finer granularity than library.

dart/sdk/lib/_internal/compiler/implementation/typechecker.dart

 // Copyright (c) 2012, 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;
 
 class TypeCheckerTask extends CompilerTask {
   TypeCheckerTask(Compiler compiler) : super(compiler);
   String get name => "Type checker";
 
@@ skipping 171 matching lines @@
 
     if (currentClass != null) {
       thisType = currentClass.computeType(compiler);
       superType = currentClass.supertype;
     }
   }
 
   LibraryElement get currentLibrary => elements.currentElement.getLibrary();
 
   reportTypeWarning(Node node, MessageKind kind, [Map arguments = const {}]) {
-    compiler.reportWarning(node, new TypeWarning(kind, arguments));
+    compiler.reportWarning(
+        node, new TypeWarning(kind, arguments, compiler.terseDiagnostics));
   }
 
   reportTypeInfo(Spannable node, MessageKind kind, [Map arguments = const {}]) {
     compiler.reportDiagnostic(compiler.spanFromSpannable(node),
         'Info: ${kind.message(arguments)}', api.Diagnostic.INFO);
   }
 
   // TODO(karlklose): remove these functions.
   DartType unhandledStatement() => StatementType.NOT_RETURNING;
   DartType unhandledExpression() => types.dynamicType;
@@ skipping 1022 matching lines @@
   visitTypedef(Typedef node) {
     // Do not typecheck [Typedef] nodes.
   }
 
   visitNode(Node node) {
     compiler.internalError(
         'Unexpected node ${node.getObjectDescription()} in the type checker.',
         node: node);
   }
 }