Make sure we throw the right NSM error when indexing out of range of a variable that can be null.

sdk/lib/_internal/compiler/implementation/ssa/optimize.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.
 
 part of ssa;
 
 abstract class OptimizationPhase {
   String get name;
   void visitGraph(HGraph graph);
 }
@@ skipping 859 matching lines @@
                                  HInstruction array,
                                  HInstruction indexArgument) {
     Compiler compiler = backend.compiler;
     bool isAssignable =
         !array.isFixedArray(compiler) && !array.isString(compiler);
     HFieldGet length = new HFieldGet(
         backend.jsIndexableLength, array, isAssignable: isAssignable);
     length.instructionType = HType.INTEGER;
     indexNode.block.addBefore(indexNode, length);
 
-    HBoundsCheck check = new HBoundsCheck(indexArgument, length);
+    HBoundsCheck check = new HBoundsCheck(indexArgument, length, array);
     indexNode.block.addBefore(indexNode, check);
     // If the index input to the bounds check was not known to be an integer
     // then we replace its uses with the bounds check, which is known to be an
     // integer.  However, if the input was already an integer we don't do this
     // because putting in a check instruction might obscure the real nature of
     // the index eg. if it is a constant.  The range information from the
     // BoundsCheck instruction is attached to the input directly by
     // visitBoundsCheck in the SsaValueRangeAnalyzer.
     if (!indexArgument.isInteger()) {
       indexArgument.replaceAllUsersDominatedBy(indexNode, check);
@@ skipping 613 matching lines @@
       // that knows it is not of a specific Type.
     }
 
     for (HIf ifUser in notIfUsers) {
       changeUsesDominatedBy(ifUser.elseBlock, input, convertedType);
       // TODO(ngeoffray): Also change uses for the then block on a HType
       // that knows it is not of a specific Type.
     }
   }
 }