Split backend implementation of EnqueuerListener

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

 // Copyright (c) 2014, 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.full_emitter;
 
 import 'dart:collection' show HashMap;
 import 'dart:convert';
 
 import 'package:js_runtime/shared/embedded_names.dart' as embeddedNames;
@@ skipping 1014 matching lines @@
         return false;
       })();
     ''');
 
     return supportsDirectProtoAccess;
   }
 
   jsAst.Expression generateLibraryDescriptor(
       LibraryElement library, Fragment fragment) {
     var uri = "";
-    if (!compiler.options.enableMinification || backend.mustPreserveUris) {
+    if (!compiler.options.enableMinification ||
+        backend.mirrorsData.mustPreserveUris) {
       uri = library.canonicalUri;
       if (uri.scheme == 'file' && compiler.options.outputUri != null) {
         uri =
             relativize(compiler.options.outputUri, library.canonicalUri, false);
       }
     }
 
     String libraryName = (!compiler.options.enableMinification ||
             backend.mirrorsData.mustRetainLibraryNames)
         ? library.libraryName
@@ skipping 33 matching lines @@
 
   void assemblePrecompiledConstructor(
       OutputUnit outputUnit,
       jsAst.Name constructorName,
       jsAst.Expression constructorAst,
       List<jsAst.Name> fields) {
     cspPrecompiledFunctionFor(outputUnit)
         .add(new jsAst.FunctionDeclaration(constructorName, constructorAst));
 
     String fieldNamesProperty = FIELD_NAMES_PROPERTY_NAME;
-    bool hasIsolateSupport = backend.hasIsolateSupport;
+    bool hasIsolateSupport = backend.backendUsage.isIsolateInUse;
     jsAst.Node fieldNamesArray;
     if (hasIsolateSupport) {
       fieldNamesArray =
           new jsAst.ArrayInitializer(fields.map(js.quoteName).toList());
     } else {
       fieldNamesArray = new jsAst.LiteralNull();
     }
 
     cspPrecompiledFunctionFor(outputUnit).add(js.statement(
         r'''
@@ skipping 525 matching lines @@
     // boilerplate JS code, like the sourcemap directives or the hash
     // itself.
     Map<OutputUnit, String> deferredLoadHashes =
         emitDeferredOutputUnits(deferredParts);
 
     deferredHashTokens.forEach((OutputUnit key, _DeferredOutputUnitHash token) {
       token.setHash(deferredLoadHashes[key]);
     });
     emitMainOutputUnit(program.mainFragment.outputUnit, mainOutput);
 
-    if (backend.requiresPreamble && !backend.htmlLibraryIsLoaded) {
+    if (backend.backendUsage.requiresPreamble && !backend.htmlLibraryIsLoaded) {
       reporter.reportHintMessage(NO_LOCATION_SPANNABLE, MessageKind.PREAMBLE);
     }
     // Return the total program size.
     return outputBuffers.values.fold(0, (a, b) => a + b.length);
   }
 
   String generateSourceMapTag(Uri sourceMapUri, Uri fileUri) {
     if (sourceMapUri != null && fileUri != null) {
       String sourceMapFileName = relativize(fileUri, sourceMapUri, false);
       return '''
@@ skipping 291 matching lines @@
     // data.
     mapping["_comment"] = "This mapping shows which compiled `.js` files are "
         "needed for a given deferred library import.";
     mapping.addAll(compiler.deferredLoadTask.computeDeferredMap());
     compiler.outputProvider(
         compiler.options.deferredMapUri.path, 'deferred_map')
       ..add(const JsonEncoder.withIndent("  ").convert(mapping))
       ..close();
   }
 }