Refactoring if block-information.

lib/compiler/implementation/native_handler.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.
 
 #library('native');
 #import('dart:uri');
 #import('leg.dart');
 #import('elements/elements.dart');
 #import('scanner/scannerlib.dart');
 #import('ssa/ssa.dart');
@@ skipping 312 matching lines @@
             'Object.prototype.$dartMethodName.call(#$params)');
         elseInstruction =
             new HForeign(jsCode, const LiteralDartString('Object'), inputs);
         builder.add(elseInstruction);
       }
 
       HConstant constant = builder.graph.addConstantString(
           new DartString.literal('$dartMethodName'));
       DartString jsCode = new DartString.literal(
           'Object.getPrototypeOf(#).hasOwnProperty(#)');
-      builder.push(new HForeign(
-          jsCode, const LiteralDartString('Object'),
-          <HInstruction>[builder.localsHandler.readThis(), constant]));
+      visitCondition() {
+        builder.push(new HForeign(
+            jsCode, const LiteralDartString('Object'),
+            <HInstruction>[builder.localsHandler.readThis(), constant]));
+      }
 
-      builder.handleIf(visitThen, visitElse);
+      builder.handleIf(visitCondition, visitThen, visitElse);
 
       HPhi phi = new HPhi.manyInputs(
           null, <HInstruction>[thenInstruction, elseInstruction]);
       builder.current.addPhi(phi);
       builder.stack.add(phi);
     }
   } else {
     // This is JS code written in a Dart file with the construct
     // native """ ... """;. It does not work well with mangling,
     // but there should currently be no clash between leg mangling
@@ skipping 11 matching lines @@
             const LiteralDartString('void'),
             <HInstruction>[jsClosure]));
       }
     });
     LiteralString jsCode = node.arguments.head;
     builder.push(new HForeign(jsCode.dartString,
                               const LiteralDartString('Object'),
                               <HInstruction>[]));
   }
 }