Fix braino that lead to dead code that contained a typo. Also add a regression test.

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 704 matching lines @@
       return graph.thisInstruction;
     }
 
     Constant constant = new ConstructedConstant(
         constantInterceptor.computeType(compiler), <Constant>[]);
     return graph.addConstant(constant);
   }
 
   HInstruction visitOneShotInterceptor(HOneShotInterceptor node) {
     HInstruction newInstruction = handleInterceptorCall(node);
-    if (newInstruction != null) return newInstruction;
+    if (newInstruction != node) return newInstruction;
 
     HInstruction constant = tryComputeConstantInterceptor(
         node.inputs[1], node.interceptedClasses);
 
     if (constant == null) return node;
 
     Selector selector = node.selector;
     // TODO(ngeoffray): make one shot interceptors know whether
     // they have side effects.
     if (selector.isGetter()) {
       HInstruction res = new HInvokeDynamicGetter(
           selector, node.element, constant, false);
-      res.inputs.add(node.intputs[1]);
+      res.inputs.add(node.inputs[1]);
       return res;
     } else if (node.selector.isSetter()) {
       HInstruction res = new HInvokeDynamicSetter(
           selector, node.element, constant, node.inputs[1], false);
-      res.inputs.add(node.intputs[2]);
+      res.inputs.add(node.inputs[2]);
       return res;
     } else {
       List<HInstruction> inputs = new List<HInstruction>.from(node.inputs);
       inputs[0] = constant;
       return new HInvokeDynamicMethod(selector, inputs, true);
     }
   }
 }
 
 class SsaCheckInserter extends HBaseVisitor implements OptimizationPhase {
@@ skipping 779 matching lines @@
     HBasicBlock block = user.block;
     block.addAfter(user, interceptor);
     block.rewrite(user, interceptor);
     block.remove(user);
 
     // The interceptor will be removed in the dead code elimination
     // phase. Note that removing it here would not work because of how
     // the [visitBasicBlock] is implemented.
   }
 }