Add Class/MemberDefinition to handle synthesized classes/members

pkg/compiler/lib/src/js_model/closure.dart

Index: pkg/compiler/lib/src/js_model/closure.dart
diff --git a/pkg/compiler/lib/src/js_model/closure.dart b/pkg/compiler/lib/src/js_model/closure.dart
index 58fa5c777e5b33559dbec10642bceec1a056b490..bd8cafbec349605493088faf96ba71db12b6a679 100644
--- a/pkg/compiler/lib/src/js_model/closure.dart
+++ b/pkg/compiler/lib/src/js_model/closure.dart
@@ -5,6 +5,7 @@
 import 'package:kernel/ast.dart' as ir;
 
 import '../closure.dart';
+import '../common.dart';
 import '../common/tasks.dart';
 import '../elements/entities.dart';
 import '../kernel/element_map.dart';
@@ -66,7 +67,10 @@ class KernelClosureConversionTask extends ClosureConversionTask<ir.Node> {
       }
       if (entity.isAbstract) return;
       if (entity.isField && !entity.isInstanceMember) {
-        ir.Field field = _elementMap.getMemberNode(entity);
+        MemberDefinition definition = _elementMap.getMemberDefinition(entity);
+        assert(definition.kind == MemberKind.regular,
+            failedAt(entity, "Unexpected member definition $definition"));
+        ir.Field field = definition.node;
         // Skip top-level/static fields without an initializer.
         if (field.initializer == null) return;
       }
@@ -86,7 +90,15 @@ class KernelClosureConversionTask extends ClosureConversionTask<ir.Node> {
       Map<ir.TreeNode, ScopeInfo> closuresToGenerate,
       ClosedWorldRefiner closedWorldRefiner) {
     if (_scopeMap.keys.contains(entity)) return;
-    ir.Node node = _elementMap.getMemberNode(entity);
+    MemberDefinition definition = _elementMap.getMemberDefinition(entity);
+    switch (definition.kind) {
+      case MemberKind.regular:
+      case MemberKind.constructor:
+        break;
+      default:
+        failedAt(entity, "Unexpected member definition $definition");
+    }
+    ir.Node node = definition.node;
     if (_scopesCapturedInClosureMap.keys.contains(node)) return;
     CapturedScopeBuilder translator = new CapturedScopeBuilder(
         _scopesCapturedInClosureMap,
@@ -114,7 +126,7 @@ class KernelClosureConversionTask extends ClosureConversionTask<ir.Node> {
       ClosedWorldRefiner closedWorldRefiner) {
     Entity entity;
     KernelClosureClass closureClass =
-        new KernelClosureClass.fromScopeInfo(info);
+        new KernelClosureClass.fromScopeInfo(info, node.location);
     if (node is ir.FunctionNode) {
       // We want the original declaration where that function is used to point
       // to the correct closure class.
@@ -153,9 +165,18 @@ class KernelClosureConversionTask extends ClosureConversionTask<ir.Node> {
   // TODO(efortuna): Eventually scopesCapturedInClosureMap[node] should always
   // be non-null, and we should just test that with an assert.
   @override
-  CapturedScope getCapturedScope(MemberEntity entity) =>
-      _scopesCapturedInClosureMap[_elementMap.getMemberNode(entity)] ??
-      const CapturedScope();
+  CapturedScope getCapturedScope(MemberEntity entity) {
+    MemberDefinition definition = _elementMap.getMemberDefinition(entity);
+    switch (definition.kind) {
+      case MemberKind.regular:
+      case MemberKind.constructor:
+      case MemberKind.constructorBody:
+        return _scopesCapturedInClosureMap[definition.node] ??
+            const CapturedScope();
+      default:
+        throw failedAt(entity, "Unexpected member definition $definition");
+    }
+  }
 
   @override
   // TODO(efortuna): Eventually scopesCapturedInClosureMap[node] should always
@@ -235,6 +256,8 @@ class KernelCapturedLoopScope extends KernelCapturedScope
 // TODO(johnniwinther): Add unittest for the computed [ClosureClass].
 class KernelClosureClass extends KernelScopeInfo
     implements ClosureRepresentationInfo, JClass {
+  final ir.Location location;
+
   // TODO(efortuna): Generate unique name for each closure class.
   final String name = 'ClosureClass';
 
@@ -244,7 +267,7 @@ class KernelClosureClass extends KernelScopeInfo
 
   final Map<Local, JField> localToFieldMap = new Map<Local, JField>();
 
-  KernelClosureClass.fromScopeInfo(KernelScopeInfo info)
+  KernelClosureClass.fromScopeInfo(KernelScopeInfo info, this.location)
       : super.from(info.thisLocal, info);
 
   // TODO(efortuna): Implement.
@@ -288,3 +311,18 @@ class KernelClosureClass extends KernelScopeInfo
 
   String toString() => '${jsElementPrefix}class($name)';
 }
+
+class ClosureClassDefinition implements ClassDefinition {
+  final ClassEntity cls;
+  final ir.Location location;
+
+  ClosureClassDefinition(this.cls, this.location);
+
+  ClassKind get kind => ClassKind.closure;
+
+  ir.Node get node =>
+      throw new UnsupportedError('ClosureClassDefinition.node for $cls');
+
+  String toString() =>
+      'ClosureClassDefinition(kind:$kind,cls:$cls,location:$location)';
+}