Do not evaluate inlined field initializations twice in a redirecting constructor.

sdk/lib/_internal/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.
 
 part of ssa;
 
 /**
  * A special element for the extra parameter taken by intercepted
  * methods. We need to override [Element.computeType] because our
  * optimizers may look at its declared type.
@@ skipping 1396 matching lines @@
         // type variables.
         assert(typeVariables.isEmpty
                || enclosingClass.typeVariables == typeVariables);
         while (!typeVariables.isEmpty) {
           localsHandler.updateLocal(typeVariables.head.element,
               graph.addConstantNull(compiler));
           typeVariables = typeVariables.tail;
         }
       }
 
-      inlinedFrom(callee, () {
-        buildFieldInitializers(callee.enclosingElement.implementation,
+      // For redirecting constructors, the fields have already been
+      // initialized by the caller.
+      if (callee.getEnclosingClass() != caller.getEnclosingClass()) {
+        inlinedFrom(callee, () {
+          buildFieldInitializers(callee.enclosingElement.implementation,
                                fieldValues);
-      });
+        });
+      }
 
       int index = 0;
       FunctionSignature params = callee.computeSignature(compiler);
       params.orderedForEachParameter((Element parameter) {
         HInstruction argument = compiledArguments[index++];
         // Because we are inlining the initializer, we must update
         // what was given as parameter. This will be used in case
         // there is a parameter check expression in the initializer.
         parameters[parameter] = argument;
         localsHandler.updateLocal(parameter, argument);
@@ skipping 4078 matching lines @@
           new HSubGraphBlockInformation(elseBranch.graph));
 
     HBasicBlock conditionStartBlock = conditionBranch.block;
     conditionStartBlock.setBlockFlow(info, joinBlock);
     SubGraph conditionGraph = conditionBranch.graph;
     HIf branch = conditionGraph.end.last;
     assert(branch is HIf);
     branch.blockInformation = conditionStartBlock.blockFlow;
   }
 }