Fix checked mode.

lib/compiler/implementation/ssa/builder.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 class Interceptors {
   Compiler compiler;
   Interceptors(Compiler this.compiler);
 
   SourceString mapOperatorToMethodName(Operator op) {
     String name = op.source.stringValue;
@@ skipping 2544 matching lines @@
   void visitLiteralString(LiteralString node) {
     stack.add(graph.addConstantString(node.dartString, node));
   }
 
   void visitStringJuxtaposition(StringJuxtaposition node) {
     if (!node.isInterpolation) {
       // This is a simple string with no interpolations.
       stack.add(graph.addConstantString(node.dartString, node));
       return;
     }
-    StringBuilderVisitor stringBuilder = new StringBuilderVisitor(this);
+    StringBuilderVisitor stringBuilder = new StringBuilderVisitor(this, node);
     stringBuilder.visit(node);
     stack.add(stringBuilder.result);
   }
 
   void visitLiteralNull(LiteralNull node) {
     stack.add(graph.addConstantNull());
   }
 
   visitNodeList(NodeList node) {
     for (Link<Node> link = node.nodes; !link.isEmpty(); link = link.tail) {
@@ skipping 131 matching lines @@
     open(joinBlock);
 
     localsHandler.mergeWith(thenLocals, joinBlock);
     HPhi phi = new HPhi.manyInputs(null,
         <HInstruction>[thenInstruction, elseInstruction]);
     joinBlock.addPhi(phi);
     stack.add(phi);
   }
 
   visitStringInterpolation(StringInterpolation node) {
-    StringBuilderVisitor stringBuilder = new StringBuilderVisitor(this);
+    StringBuilderVisitor stringBuilder = new StringBuilderVisitor(this, node);
     stringBuilder.visit(node);
     stack.add(stringBuilder.result);
   }
 
   visitStringInterpolationPart(StringInterpolationPart node) {
     // The parts are iterated in visitStringInterpolation.
     compiler.internalError('visitStringInterpolation should not be called',
                            node: node);
   }
 
@@ skipping 656 matching lines @@
 
 /**
  * Visitor that handles generation of string literals (LiteralString,
  * StringInterpolation), and otherwise delegates to the given visitor for
  * non-literal subexpressions.
  * TODO(lrn): Consider whether to handle compile time constant int/boolean
  * expressions as well.
  */
 class StringBuilderVisitor extends AbstractVisitor {
   final SsaBuilder builder;
+  final Node node;
 
   /**
    * The string value generated so far.
    */
   HInstruction result = null;
 
-  StringBuilderVisitor(this.builder);
+  StringBuilderVisitor(this.builder, this.node);
 
   void visit(Node node) {
     node.accept(this);
   }
 
   visitNode(Node node) {
     builder.compiler.internalError('unexpected node', node: node);
   }
 
   void visitExpression(Node node) {
@@ skipping 13 matching lines @@
 
   void visitStringJuxtaposition(StringJuxtaposition node) {
     node.visitChildren(this);
   }
 
   void visitNodeList(NodeList node) {
      node.visitChildren(this);
   }
 
   HInstruction concat(HInstruction left, HInstruction right) {
-    HInstruction instruction = new HStringConcat(left, right);
+    HInstruction instruction = new HStringConcat(left, right, node);
     builder.add(instruction);
     return instruction;
   }
 }