Add KernelCodegenWorkItem stub

With this change we can run the compilation of hello_world from .dill
(with --read-dill --disable-type-inference) to where we need to run
the KernelSsaBuilder.

R=sigmund@google.com

Review-Url: https://codereview.chromium.org/2888413004 .

pkg/compiler/lib/src/common/codegen.dart

@@ -5,7 +5,7 @@
 library dart2js.common.codegen;
 
 import '../elements/elements.dart'
-    show AsyncMarker, ClassElement, LocalFunctionElement, MemberElement;
+    show AsyncMarker, ClassElement, LocalFunctionElement;
 import '../elements/entities.dart';
 import '../elements/types.dart' show DartType, InterfaceType;
 import '../universe/use.dart' show ConstantUse, DynamicUse, StaticUse, TypeUse;
@@ -110,12 +110,11 @@ class _CodegenImpact extends WorldImpactBuilderImpl implements CodegenImpact {
 // TODO(johnniwinther): Split this class into interface and implementation.
 // TODO(johnniwinther): Move this implementation to the JS backend.
 class CodegenRegistry {
-  final MemberElement currentElement;
+  final MemberEntity currentElement;
   final _CodegenImpact worldImpact;
 
-  CodegenRegistry(MemberElement currentElement)
-      : this.currentElement = currentElement,
-        this.worldImpact = new _CodegenImpact();
+  CodegenRegistry(this.currentElement)
+      : this.worldImpact = new _CodegenImpact();
 
   bool get isForResolution => false;
 

pkg/compiler/lib/src/inferrer/inferrer_engine.dart

@@ -46,7 +46,7 @@ class InferrerEngine {
   final Map<Element, TypeInformation> defaultTypeOfParameter =
       new Map<Element, TypeInformation>();
   final WorkQueue workQueue = new WorkQueue();
-  final Element mainElement;
+  final FunctionEntity mainElement;
   final Set<Element> analyzedElements = new Set<Element>();
 
   /// The maximum number of times we allow a node in the graph to

pkg/compiler/lib/src/inferrer/type_graph_inferrer.dart

@@ -63,7 +63,7 @@ class TypeGraphInferrer implements TypesInferrer {
 
   TypeMask get _dynamicType => commonMasks.dynamicType;
 
-  void analyzeMain(Element main) {
+  void analyzeMain(FunctionEntity main) {
     inferrer =
         new InferrerEngine(compiler, closedWorld, closedWorldRefiner, main);
     inferrer.runOverAllElements();

pkg/compiler/lib/src/js_backend/codegen_listener.dart

@@ -239,16 +239,15 @@ class CodegenEnqueuerListener extends EnqueuerListener {
   }
 
   @override
-  WorldImpact registerUsedElement(MemberElement member) {
+  WorldImpact registerUsedElement(MemberEntity member) {
     WorldImpactBuilderImpl worldImpact = new WorldImpactBuilderImpl();
     _customElementsAnalysis.registerStaticUse(member);
 
     if (member.isFunction && member.isInstanceMember) {
-      MethodElement method = member;
-      ClassElement cls = method.enclosingClass;
-      if (method.name == Identifiers.call &&
-          !cls.typeVariables.isEmpty &&
-          _rtiNeed.methodNeedsRti(method)) {
+      ClassEntity cls = member.enclosingClass;
+      if (member.name == Identifiers.call &&
+          _elementEnvironment.isGenericClass(cls) &&
+          _rtiNeed.methodNeedsRti(member)) {
         worldImpact.addImpact(_registerComputeSignature());
       }
     }

pkg/compiler/lib/src/kernel/kernel_strategy.dart

@@ -9,7 +9,7 @@ import '../backend_strategy.dart';
 import '../common.dart';
 import '../common_elements.dart';
 import '../common/backend_api.dart';
-import '../common/codegen.dart' show CodegenWorkItem;
+import '../common/codegen.dart' show CodegenRegistry, CodegenWorkItem;
 import '../common/resolution.dart';
 import '../common/tasks.dart';
 import '../common/work.dart';
@@ -231,7 +231,8 @@ class MirrorsResolutionAnalysisImpl implements MirrorsResolutionAnalysis {
 
   @override
   MirrorsCodegenAnalysis close() {
-    throw new UnimplementedError('MirrorsResolutionAnalysisImpl.close');
+    // TODO(johnniwinther): Implement this.
+    return new MirrorsCodegenAnalysisImpl();
   }
 
   @override
@@ -255,7 +256,6 @@ class KernelBackendStrategy implements BackendStrategy {
   void convertClosures(ClosedWorldRefiner closedWorldRefiner) {
     // TODO(johnniwinther,efortuna): Compute closure classes for kernel based
     // elements.
-    throw new UnimplementedError('KernelBackendStrategy.createClosureClasses');
   }
 
   @override
@@ -273,9 +273,35 @@ class KernelBackendStrategy implements BackendStrategy {
   }
 }
 
+class MirrorsCodegenAnalysisImpl implements MirrorsCodegenAnalysis {
+  @override
+  int get preMirrorsMethodCount {
+    throw new UnimplementedError(
+        'MirrorsCodegenAnalysisImpl.preMirrorsMethodCount');
+  }
+
+  @override
+  void onQueueEmpty(Enqueuer enqueuer, Iterable<ClassEntity> recentClasses) {
+    throw new UnimplementedError('MirrorsCodegenAnalysisImpl.onQueueEmpty');
+  }
+}
+
 class KernelCodegenWorkItemBuilder implements WorkItemBuilder {
   @override
   CodegenWorkItem createWorkItem(MemberEntity entity) {
-    throw new UnimplementedError('KernelCodegenWorkItemBuilder.createWorkItem');
+    return new KernelCodegenWorkItem(entity);
+  }
+}
+
+class KernelCodegenWorkItem extends CodegenWorkItem {
+  final MemberEntity element;
+  final CodegenRegistry registry;
+
+  KernelCodegenWorkItem(this.element) : registry = new CodegenRegistry(element);
+
+  @override
+  WorldImpact run() {
+    // TODO(johnniwinther): Build SSA graph from kernel and run codegen on it.
+    return const WorldImpact();
   }
 }

pkg/compiler/lib/src/source_file_provider.dart

@@ -206,7 +206,9 @@ class FormattingDiagnosticHandler implements CompilerDiagnostics {
       print('${color(message)}');
     } else {
       SourceFile file = provider.sourceFiles[uri];
-      if (file != null) {
+      // TODO(johnniwinther): Remove the '.dill' hack; add support for binary
+      // files to avoid crashes on trying to decode .dill binaries as utf8.
+      if (file != null && !file.filename.endsWith('.dill')) {
         print(file.getLocationMessage(color(message), begin, end,
             colorize: color));
       } else {

pkg/compiler/lib/src/types/types.dart

@@ -9,6 +9,7 @@ import '../common.dart' show invariant;
 import '../common/tasks.dart' show CompilerTask;
 import '../compiler.dart' show Compiler;
 import '../elements/elements.dart';
+import '../elements/entities.dart';
 import '../inferrer/type_graph_inferrer.dart' show TypeGraphInferrer;
 import '../inferrer/type_system.dart';
 import '../tree/tree.dart';
@@ -171,7 +172,7 @@ class GlobalTypeInferenceElementData {
 
 /// API to interact with the global type-inference engine.
 abstract class TypesInferrer {
-  void analyzeMain(Element element);
+  void analyzeMain(FunctionEntity element);
   TypeMask getReturnTypeOfElement(Element element);
   TypeMask getTypeOfElement(Element element);
   TypeMask getTypeForNewList(Element owner, Node node);
@@ -271,7 +272,7 @@ class GlobalTypeInferenceTask extends CompilerTask {
         super(compiler.measurer);
 
   /// Runs the global type-inference algorithm once.
-  void runGlobalTypeInference(MethodElement mainElement,
+  void runGlobalTypeInference(FunctionEntity mainElement,
       ClosedWorld closedWorld, ClosedWorldRefiner closedWorldRefiner) {
     measure(() {
       typesInferrerInternal ??=