Move dart2jslib parts into separate libraries.

pkg/compiler/lib/src/use_unused_api.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.
 
 /// This file use methods that aren't used by dart2js.dart, but that we wish to
 /// keep anyway. This might be general API that isn't currently in use,
 /// debugging aids, or API only used for testing (see TODO below).
 
 library dart2js.use_unused_api;
 
@@ skipping 19 matching lines @@
 import 'inferrer/type_graph_inferrer.dart' as type_graph_inferrer;
 import 'io/line_column_provider.dart' as io;
 import 'io/source_map_builder.dart' as io;
 import 'js/js.dart' as js;
 import 'js_backend/js_backend.dart' as js_backend;
 import 'js_emitter/js_emitter.dart' as js_emitter;
 import 'js_emitter/full_emitter/emitter.dart' as full;
 import 'js_emitter/program_builder/program_builder.dart' as program_builder;
 import 'resolution/semantic_visitor.dart' as semantic_visitor;
 import 'resolution/operators.dart' as operators;
+import 'script.dart';
 import 'source_file_provider.dart' as source_file_provider;
 import 'ssa/ssa.dart' as ssa;
 import 'tree/tree.dart' as tree;
 import 'util/util.dart' as util;
+import 'world.dart';
 
 import 'scanner/scannerlib.dart' show
     PartialClassElement,
     PartialFunctionElement;
 
 class ElementVisitor extends elements_visitor.BaseElementVisitor {
   visitElement(e, a) {}
 }
 
 void main(List<String> arguments) {
@@ skipping 195 matching lines @@
   map..addFirst(null, null, null)
      ..forEachLine(null)
      ..getFirstElementsInLine(null)
      ..forEachColumn(null, null);
   provider.getOffset(null, null);
 }
 
 usedByTests() {
   // TODO(ahe): We should try to avoid including API used only for tests. In
   // most cases, such API can be moved to a test library.
-  dart2jslib.World world = null;
+  World world = null;
   dart2jslib.Compiler compiler = null;
   compiler.currentlyInUserCode();
   type_graph_inferrer.TypeGraphInferrer typeGraphInferrer = null;
   source_file_provider.SourceFileProvider sourceFileProvider = null;
   sourceFileProvider.getSourceFile(null);
   world.hasAnyUserDefinedGetter(null, null);
   world.subclassesOf(null);
   world.classHierarchyNode(null);
   typeGraphInferrer.getCallersOf(null);
   dart_types.Types.sorted(null);
@@ skipping 34 matching lines @@
 useTypes() {
   new dart_types.ResolvedTypedefType(null, null, null).unalias(null);
 }
 
 useCodeEmitterTask(js_emitter.CodeEmitterTask codeEmitterTask) {
   full.Emitter fullEmitter = codeEmitterTask.emitter;
   fullEmitter.clearCspPrecompiledNodes();
   fullEmitter.buildLazilyInitializedStaticField(null, isolateProperties: null);
 }
 
-useScript(dart2jslib.Script script) {
+useScript(Script script) {
   script.copyWithFile(null);
 }
 
 useProgramBuilder(program_builder.ProgramBuilder builder) {
   builder.buildMethodHackForIncrementalCompilation(null);
   builder.buildFieldsHackForIncrementalCompilation(null);
 }
 
 useSemanticVisitor() {
   operators.UnaryOperator.fromKind(null);
   operators.BinaryOperator.fromKind(null);
   new semantic_visitor.BulkSendVisitor()
       ..apply(null, null)
       ..visitSuperFieldFieldCompound(null, null, null, null, null, null);
   new semantic_visitor.TraversalVisitor(null).apply(null, null);
   new semantic_visitor.BulkDeclarationVisitor().apply(null, null);
 }
 
 class TreeVisitor1 extends tree_ir.ExpressionVisitor1
                       with tree_ir.StatementVisitor1 {
   noSuchMethod(inv) {}
 }
 
 useTreeVisitors() {
   new TreeVisitor1().visitExpression(null, null);
   new TreeVisitor1().visitStatement(null, null);
 }