Add ScopeInfo class for variable information that doesn't actually involve closures.

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

Index: pkg/compiler/lib/src/kernel/closure.dart
diff --git a/pkg/compiler/lib/src/kernel/closure.dart b/pkg/compiler/lib/src/kernel/closure.dart
index 9354ae3c29280f351abcde25a64792e1cb9b5ab2..d62b26cbd75aa79087de472363ecceb0311385f5 100644
--- a/pkg/compiler/lib/src/kernel/closure.dart
+++ b/pkg/compiler/lib/src/kernel/closure.dart
@@ -97,6 +97,12 @@ class KernelClosureConversionTask extends ClosureConversionTask<ir.Node> {
     return const ClosureAnalysisInfo();
   }
 
+  @override
+  ScopeInfo getScopeInfo(Entity entity) {
+    // TODO(efortuna): Specialize this function from the one below.
+    return getClosureRepresentationInfo(entity);
+  }
+
   /// TODO(johnniwinther,efortuna): Implement this.
   @override
   LoopClosureRepresentationInfo getClosureRepresentationInfoForLoop(