Split getClosureRepresentationInfo into MemberEntity and (ir/ast) nodes

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

Index: pkg/compiler/lib/src/inferrer/builder.dart
diff --git a/pkg/compiler/lib/src/inferrer/builder.dart b/pkg/compiler/lib/src/inferrer/builder.dart
index 1c6bbe299e1c24a395a99d38d32c04b9391c9395..e050a7db7b31c068a3009c0187b38194e0143543 100644
--- a/pkg/compiler/lib/src/inferrer/builder.dart
+++ b/pkg/compiler/lib/src/inferrer/builder.dart
@@ -923,7 +923,7 @@ class ElementGraphBuilder extends ast.Visitor<TypeInformation>
     // previous analysis of [outermostElement].
     ClosureRepresentationInfo closureData = compiler
         .backendStrategy.closureDataLookup
-        .getClosureRepresentationInfo(analyzedElement);
+        .getClosureInfoForMember(analyzedElement);
     closureData.forEachCapturedVariable((variable, field) {
       locals.setCaptured(variable, field);
     });
@@ -1118,9 +1118,8 @@ class ElementGraphBuilder extends ast.Visitor<TypeInformation>
     // Record the types of captured non-boxed variables. Types of
     // these variables may already be there, because of an analysis of
     // a previous closure.
-    ClosureRepresentationInfo nestedClosureData = compiler
-        .backendStrategy.closureDataLookup
-        .getClosureRepresentationInfo(element);
+    ClosureRepresentationInfo nestedClosureData =
+        compiler.backendStrategy.closureDataLookup.getClosureInfo(node);
     nestedClosureData.forEachCapturedVariable((variable, field) {
       if (!nestedClosureData.isVariableBoxed(variable)) {
         if (variable == nestedClosureData.thisLocal) {