dart2js cps: Fix for try/catch.

pkg/compiler/lib/src/cps_ir/cps_ir_builder.dart

 // Copyright (c) 2013, 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.
 
 library dart2js.ir_builder;
 
 import '../constants/constant_system.dart';
 import '../constants/expressions.dart';
 import '../constants/values.dart' show PrimitiveConstantValue;
 import '../dart_types.dart';
@@ skipping 1841 matching lines @@
                             elseContinuation));
       catchBody =
           new ir.LetCont(checkType,
               new ir.TypeOperator(exceptionParameter, clause.type, checkType,
                                   isTypeTest: true));
     }
 
     List<ir.Parameter> catchParameters =
         <ir.Parameter>[exceptionParameter, traceParameter];
     ir.Continuation catchContinuation = new ir.Continuation(catchParameters);
-    catchContinuation.body = catchBody;
+    catchBuilder.add(catchBody);
+    catchContinuation.body = catchBuilder._root;
 
     tryCatchBuilder.add(
         new ir.LetHandler(catchContinuation, tryBuilder._root));
     add(new ir.LetCont(join.continuation, tryCatchBuilder._root));
     environment = join.environment;
   }
 
   /// Create a return statement `return value;` or `return;` if [value] is
   /// null.
   void buildReturn([ir.Primitive value]) {
@@ skipping 595 matching lines @@
   /// Create a read access of [local] variable or parameter.
   @override
   ir.Primitive _buildLocalGet(LocalElement local) {
     assert(isOpen);
     ClosureLocation location = jsState.boxedVariables[local];
     if (location != null) {
       ir.Primitive result = new ir.GetField(environment.lookup(location.box),
                                             location.field);
       result.useElementAsHint(local);
       return addPrimitive(result);
+    } else if (isInMutableVariable(local)) {
+      return addPrimitive(new ir.GetMutableVariable(getMutableVariable(local)));
     } else {
       return environment.lookup(local);
     }
   }
 
   /// Create a write access to [local] variable or parameter with the provided
   /// [value].
   @override
   ir.Primitive buildLocalVariableSet(LocalElement local, ir.Primitive value) {
     assert(isOpen);
     ClosureLocation location = jsState.boxedVariables[local];
     if (location != null) {
       add(new ir.SetField(environment.lookup(location.box),
                           location.field,
                           value));
+    } else if (isInMutableVariable(local)) {
+      add(new ir.SetMutableVariable(getMutableVariable(local), value));
     } else {
       value.useElementAsHint(local);
       environment.update(local, value);
     }
     return value;
   }
 
   void _enterForLoopInitializer(ClosureScope scope,
                                 List<LocalElement> loopVariables) {
     if (scope == null) return;
@@ skipping 225 matching lines @@
 }
 
 /// Synthetic parameter to a JavaScript factory method that takes the type
 /// argument given for the type variable [variable].
 class TypeInformationParameter implements Local {
   final TypeVariableElement variable;
   final ExecutableElement executableContext;
   TypeInformationParameter(this.variable, this.executableContext);
   String get name => variable.name;
 }