Add StaticUse for more precise registration of statically known element use.

pkg/compiler/lib/src/compiler.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.
 
 library dart2js.compiler_base;
 
 import 'dart:async' show
     EventSink,
     Future;
 
@@ skipping 114 matching lines @@
     TypeAnnotation;
 import 'typechecker.dart' show
     TypeCheckerTask;
 import 'types/types.dart' as ti;
 import 'universe/call_structure.dart' show
     CallStructure;
 import 'universe/selector.dart' show
     Selector;
 import 'universe/universe.dart' show
     Universe;
+import 'universe/use.dart' show
+    StaticUse;
 import 'universe/world_impact.dart' show
     WorldImpact;
 import 'util/util.dart' show
     Link,
     Setlet;
 import 'world.dart' show
     World;
 
 abstract class Compiler {
 
@@ skipping 753 matching lines @@
       if (parameters.requiredParameterCount > 2) {
         int index = 0;
         parameters.orderedForEachParameter((Element parameter) {
           if (index++ < 2) return;
           errorElement = new ErroneousElementX(
               MessageKind.MAIN_WITH_EXTRA_PARAMETER, {'main': Identifiers.main},
               Identifiers.main,
               parameter);
           mainFunction = backend.helperForMainArity();
           // Don't warn about main not being used:
-          enqueuer.resolution.registerStaticUse(main);
+          enqueuer.resolution.registerStaticUse(new StaticUse.foreignUse(main));
         });
       }
     }
     if (mainFunction == null) {
       if (errorElement == null && !analyzeOnly && !analyzeAll) {
         reporter.internalError(mainApp, "Problem with '${Identifiers.main}'.");
       } else {
         mainFunction = errorElement;
       }
     }
@@ skipping 1128 matching lines @@
     if (_otherDependencies == null) {
       _otherDependencies = new Setlet<Element>();
     }
     _otherDependencies.add(element.implementation);
   }
 
   Iterable<Element> get otherDependencies {
     return _otherDependencies != null ? _otherDependencies : const <Element>[];
   }
 }