dart2js: add skeleton of startup-emitter.

pkg/compiler/lib/src/js_emitter/startup_emitter/emitter.dart

-// Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
+// Copyright (c) 2015, 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.js_emitter.lazy_emitter;
+library dart2js.js_emitter.startup_emitter;
 
 import 'package:js_runtime/shared/embedded_names.dart' show
     JsBuiltin,
     METADATA,
     TYPES;
 
 import '../program_builder/program_builder.dart' show ProgramBuilder;
 import '../model.dart';
 import 'model_emitter.dart';
 import '../../common.dart';
 import '../../elements/elements.dart' show FieldElement;
 import '../../js/js.dart' as js;
 
 import '../../js_backend/js_backend.dart' show
-    JavaScriptBackend,
-    Namer;
+JavaScriptBackend,
+Namer;
 
 import '../js_emitter.dart' show
     NativeEmitter;
 
 import '../js_emitter.dart' as emitterTask show
     Emitter;
 
 import '../../util/util.dart' show
     NO_LOCATION_SPANNABLE;
 
 class Emitter implements emitterTask.Emitter {
   final Compiler _compiler;
   final Namer namer;
   final ModelEmitter _emitter;
 
   JavaScriptBackend get _backend => _compiler.backend;
 
   Emitter(Compiler compiler, Namer namer, NativeEmitter nativeEmitter)
       : this._compiler = compiler,
         this.namer = namer,
         _emitter = new ModelEmitter(compiler, namer, nativeEmitter);
 
   @override
   int emitProgram(ProgramBuilder programBuilder) {
     Program program = programBuilder.buildProgram();
     return _emitter.emitProgram(program);
   }
 
-  // TODO(floitsch): copied from full emitter. Adjust or share.
   @override
   bool isConstantInlinedOrAlreadyEmitted(ConstantValue constant) {
     return _emitter.isConstantInlinedOrAlreadyEmitted(constant);
   }
 
-  // TODO(floitsch): copied from full emitter. Adjust or share.
   @override
   int compareConstants(ConstantValue a, ConstantValue b) {
     return _emitter.compareConstants(a, b);
   }
 
   @override
   js.Expression constantReference(ConstantValue value) {
     return _emitter.generateConstantReference(value);
   }
 
@@ skipping 11 matching lines @@
   js.PropertyAccess _globalPropertyAccess(Element element) {
     js.Name name = namer.globalPropertyName(element);
     js.PropertyAccess pa = new js.PropertyAccess(
         new js.VariableUse(namer.globalObjectFor(element)), name);
     return pa;
   }
 
   @override
   js.Expression isolateLazyInitializerAccess(FieldElement element) {
     return js.js('#.#', [namer.globalObjectFor(element),
-                         namer.lazyInitializerName(element)]);
+    namer.lazyInitializerName(element)]);
   }
 
   @override
   js.Expression isolateStaticClosureAccess(FunctionElement element) {
     return _emitter.generateStaticClosureAccess(element);
   }
 
   @override
   js.PropertyAccess staticFieldAccess(FieldElement element) {
     return _globalPropertyAccess(element);
@@ skipping 12 matching lines @@
   @override
   js.PropertyAccess prototypeAccess(ClassElement element,
                                     bool hasBeenInstantiated) {
     js.Expression constructor =
         hasBeenInstantiated ? constructorAccess(element) : typeAccess(element);
     return js.js('#.prototype', constructor);
   }
 
   @override
   js.Expression interceptorClassAccess(ClassElement element) {
-    // Some interceptors are eagerly constructed. However, native interceptors
-    // aren't.
-    return js.js('#.ensureResolved()', _globalPropertyAccess(element));
+    return _globalPropertyAccess(element);
   }
 
   @override
   js.Expression typeAccess(Element element) {
-    // TODO(floitsch): minify 'ensureResolved'.
-    // TODO(floitsch): don't emit `ensureResolved` for eager classes.
-    return js.js('#.ensureResolved()', _globalPropertyAccess(element));
+    return _globalPropertyAccess(element);
   }
 
   @override
   js.Template templateForBuiltin(JsBuiltin builtin) {
     String typeNameProperty = ModelEmitter.typeNameProperty;
 
     switch (builtin) {
       case JsBuiltin.dartObjectConstructor:
         return js.js.expressionTemplateYielding(
             typeAccess(_compiler.objectClass));
 
       case JsBuiltin.isCheckPropertyToJsConstructorName:
         int isPrefixLength = namer.operatorIsPrefix.length;
         return js.js.expressionTemplateFor('#.substring($isPrefixLength)');
 
       case JsBuiltin.isFunctionType:
         return _backend.rti.representationGenerator.templateForIsFunctionType;
 
       case JsBuiltin.rawRtiToJsConstructorName:
         return js.js.expressionTemplateFor("#.$typeNameProperty");
 
       case JsBuiltin.rawRuntimeType:
         return js.js.expressionTemplateFor("#.constructor");
 
       case JsBuiltin.createFunctionTypeRti:
         return _backend.rti.representationGenerator
-            .templateForCreateFunctionType;
+        .templateForCreateFunctionType;
 
       case JsBuiltin.isSubtype:
-        // TODO(floitsch): move this closer to where is-check properties are
-        // built.
+      // TODO(floitsch): move this closer to where is-check properties are
+      // built.
         String isPrefix = namer.operatorIsPrefix;
         return js.js.expressionTemplateFor("('$isPrefix' + #) in #.prototype");
 
       case JsBuiltin.isGivenTypeRti:
         return js.js.expressionTemplateFor('#.$typeNameProperty === #');
 
       case JsBuiltin.getMetadata:
-        return _emitter.templateForReadMetadata;
+        String metadataAccess =
+            _emitter.generateEmbeddedGlobalAccessString(METADATA);
+        return js.js.expressionTemplateFor("$metadataAccess[#]");
 
       case JsBuiltin.getType:
-        return _emitter.templateForReadType;
+        String typesAccess =
+            _emitter.generateEmbeddedGlobalAccessString(TYPES);
+        return js.js.expressionTemplateFor("$typesAccess[#]");
 
       default:
         _compiler.internalError(NO_LOCATION_SPANNABLE,
-                                "Unhandled Builtin: $builtin");
+            "Unhandled Builtin: $builtin");
         return null;
     }
   }
 
   @override
   void invalidateCaches() {
   }
 }