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pkg/compiler/lib/src/js_backend/backend.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 js_backend.backend;
 
 import '../common.dart';
 import '../common/backend_api.dart'
     show ForeignResolver, NativeRegistry, ImpactTransformer;
 import '../common/codegen.dart' show CodegenWorkItem;
@@ skipping 924 matching lines @@
   String getGeneratedCode(Element element) {
     assert(invariant(element, element.isDeclaration));
     return jsAst.prettyPrint(generatedCode[element], compiler.options);
   }
 
   /// Generates the output and returns the total size of the generated code.
   int assembleProgram(ClosedWorld closedWorld) {
     int programSize = emitter.assembleProgram(namer, closedWorld);
     noSuchMethodRegistry.emitDiagnostic(reporter);
     int totalMethodCount = generatedCode.length;
-    if (totalMethodCount != mirrorsCodegenAnalysis.preMirrorsMethodCount) {
+    // TODO(johnniwinther): Support `preMirrorsMethodCount` for entities.
+    if (mirrorsCodegenAnalysis.preMirrorsMethodCount != null &&
+        totalMethodCount != mirrorsCodegenAnalysis.preMirrorsMethodCount) {
       int mirrorCount =
           totalMethodCount - mirrorsCodegenAnalysis.preMirrorsMethodCount;
       double percentage = (mirrorCount / totalMethodCount) * 100;
       DiagnosticMessage hint =
           reporter.createMessage(compiler.mainApp, MessageKind.MIRROR_BLOAT, {
         'count': mirrorCount,
         'total': totalMethodCount,
         'percentage': percentage.round()
       });
 
@@ skipping 224 matching lines @@
   MethodElement helperForMainArity() => commonElements.mainHasTooManyParameters;
 
   /// Enable deferred loading. Returns `true` if the backend supports deferred
   /// loading.
   bool enableDeferredLoadingIfSupported(Spannable node) => true;
 
   /// Enable compilation of code with compile time errors. Returns `true` if
   /// supported by the backend.
   bool enableCodegenWithErrorsIfSupported(Spannable node) => true;
 
-  jsAst.Expression rewriteAsync(
-      FunctionElement element, jsAst.Expression code) {
+  jsAst.Expression rewriteAsync(MethodElement element, jsAst.Expression code) {
     AsyncRewriterBase rewriter = null;
     jsAst.Name name = namer.methodPropertyName(element);
     switch (element.asyncMarker) {
       case AsyncMarker.ASYNC:
         rewriter = new AsyncRewriter(reporter, element,
             asyncStart:
                 emitter.staticFunctionAccess(commonElements.asyncHelperStart),
             asyncAwait:
                 emitter.staticFunctionAccess(commonElements.asyncHelperAwait),
             asyncReturn:
@@ skipping 163 matching lines @@
 
   bool canUseAliasedSuperMember(MemberEntity member, Selector selector) {
     return !selector.isGetter;
   }
 
   /// Returns `true` if [member] is called from a subclass via `super`.
   bool isAliasedSuperMember(MemberEntity member) {
     return _aliasedSuperMembers.contains(member);
   }
 }