Refactor LoopHandler to avoid calling KernelAstAdapter.getNode

pkg/compiler/lib/src/ssa/loop_handler.dart

Index: pkg/compiler/lib/src/ssa/loop_handler.dart
diff --git a/pkg/compiler/lib/src/ssa/loop_handler.dart b/pkg/compiler/lib/src/ssa/loop_handler.dart
index 6e7ad540b2594492c0e9f7f5327ea04623d86d52..48095be15dba8874a5240b220ccc229d9960bd22 100644
--- a/pkg/compiler/lib/src/ssa/loop_handler.dart
+++ b/pkg/compiler/lib/src/ssa/loop_handler.dart
@@ -4,6 +4,7 @@
 
 import 'package:kernel/ast.dart' as ir;
 
+import '../closure.dart';
 import '../elements/elements.dart' show JumpTarget, LabelDefinition;
 import '../io/source_information.dart';
 import '../tree/tree.dart' as ast;
@@ -38,7 +39,7 @@ abstract class LoopHandler<T> {
     //    goto loop-entry;
     //  loop-exit:
 
-    builder.localsHandler.startLoop(getNode(loop));
+    builder.localsHandler.startLoop(getClosureScopeForLoop(loop));
 
     // The initializer.
     SubExpression initializerGraph = null;
@@ -73,7 +74,7 @@ abstract class LoopHandler<T> {
     conditionEndBlock.addSuccessor(beginBodyBlock);
     builder.open(beginBodyBlock);
 
-    builder.localsHandler.enterLoopBody(getNode(loop));
+    builder.localsHandler.enterLoopBody(getClosureScopeForLoop(loop));
     body();
 
     SubGraph bodyGraph = new SubGraph(beginBodyBlock, builder.lastOpenedBlock);
@@ -122,7 +123,7 @@ abstract class LoopHandler<T> {
             updateBlock);
       }
 
-      builder.localsHandler.enterLoopUpdates(getNode(loop));
+      builder.localsHandler.enterLoopUpdates(getClosureScopeForLoop(loop));
 
       update();
 
@@ -287,8 +288,8 @@ abstract class LoopHandler<T> {
   /// Returns the jump target defined by [node].
   JumpTarget getTargetDefinition(T node);
 
-  /// Returns the corresponding AST node for [node].
-  ast.Node getNode(T node);
+  /// Returns closure scope data for [node].
+  ClosureScope getClosureScopeForLoop(T node);
 
   /// Determine what kind of loop [node] represents.
   ///
@@ -322,7 +323,9 @@ class SsaLoopHandler extends LoopHandler<ast.Node> {
   }
 
   @override
-  ast.Node getNode(ast.Node node) => node;
+  ClosureScope getClosureScopeForLoop(ast.Node node) {
+    return builder.localsHandler.closureData.capturingScopes[node];
+  }
 
   @override
   int loopKind(ast.Node node) => node.accept(const _SsaLoopTypeVisitor());
@@ -364,11 +367,14 @@ class KernelLoopHandler extends LoopHandler<ir.TreeNode> {
       builder.createJumpHandler(node, isLoopJump: isLoopJump);
 
   @override
-  ast.Node getNode(ir.TreeNode node) => astAdapter.getNode(node);
+  ClosureScope getClosureScopeForLoop(ir.TreeNode node) {
+    return builder.localsMap
+        .getClosureScopeForLoop(builder.localsHandler.closureData, node);
+  }
 
   @override
   JumpTarget getTargetDefinition(ir.TreeNode node) =>
-      astAdapter.getJumpTarget(node);
+      builder.localsMap.getJumpTarget(node);
 
   @override
   int loopKind(ir.TreeNode node) => node.accept(new _KernelLoopTypeVisitor());