Is checks on the right hand side of an || used in an 'if' do not apply to the then branch of that i…

tests/compiler/dart2js/simple_inferrer_test.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.
 
 import 'package:expect/expect.dart';
 import "package:async_helper/async_helper.dart";
 import
     '../../../sdk/lib/_internal/compiler/implementation/types/types.dart'
     show TypeMask;
 
@@ skipping 216 matching lines @@
   var c = topLevelGetter();
   if (c != null && c is! bool && c is! int) {
     return 42;
   } else if (c is String) {
     return c;
   } else {
     return 68;
   }
 }
 
+testIsCheck21(a) {
+  if (a is int || a is List) {
+    return a;
+  } else {
+    return 42;
+  }
+}
+
+testIsCheck22(a) {
+  return (a is int || a is List) ? a : 42;
+}
+
 testIf1(a) {
   var c = null;
   if (a) {
     c = 10;
   } else {
   }
   return c;
 }
 
 testIf2(a) {
@@ skipping 291 matching lines @@
   testIsCheck11(topLevelGetter());
   testIsCheck12(topLevelGetter());
   testIsCheck13(topLevelGetter());
   testIsCheck14(topLevelGetter());
   testIsCheck15(topLevelGetter());
   testIsCheck16(topLevelGetter());
   testIsCheck17(topLevelGetter());
   testIsCheck18(topLevelGetter());
   testIsCheck19(topLevelGetter());
   testIsCheck20();
+  testIsCheck21(topLevelGetter());
+  testIsCheck22(topLevelGetter());
   testIf1(topLevelGetter());
   testIf2(topLevelGetter());
   returnAsString();
   returnIntAsNum();
   returnAsTypedef();
   returnTopLevelGetter();
   testDeadCode();
   testLabeledIf();
   testSwitch1();
   testSwitch2();
@@ skipping 84 matching lines @@
     checkReturn('testIsCheck11', intType);
     checkReturn('testIsCheck12', typesTask.dynamicType);
     checkReturn('testIsCheck13', intType);
     checkReturn('testIsCheck14', typesTask.dynamicType);
     checkReturn('testIsCheck15', intType);
     checkReturn('testIsCheck16', typesTask.dynamicType);
     checkReturn('testIsCheck17', intType);
     checkReturn('testIsCheck18', typesTask.dynamicType);
     checkReturn('testIsCheck19', typesTask.dynamicType);
     checkReturn('testIsCheck20', typesTask.dynamicType.nonNullable());
+    checkReturn('testIsCheck21', typesTask.dynamicType);
+    checkReturn('testIsCheck22', typesTask.dynamicType);
     checkReturn('testIf1', typesTask.intType.nullable());
     checkReturn('testIf2', typesTask.intType.nullable());
     checkReturn('returnAsString',
         new TypeMask.subtype(compiler.stringClass.computeType(compiler)));
     checkReturn('returnIntAsNum', typesTask.intType);
     checkReturn('returnAsTypedef', typesTask.functionType.nullable());
     checkReturn('returnTopLevelGetter', typesTask.intType);
     checkReturn('testDeadCode', typesTask.intType);
     checkReturn('testLabeledIf', typesTask.intType.nullable());
     checkReturn('testSwitch1', typesTask.intType
@@ skipping 51 matching lines @@
     checkFactoryConstructor('A', '');
 
     checkReturn('testCascade1', typesTask.growableListType);
     checkReturn('testCascade2', new TypeMask.nonNullExact(
         typesTask.rawTypeOf(findElement(compiler, 'CascadeHelper'))));
     checkReturn('testSpecialization1', typesTask.numType);
     checkReturn('testSpecialization2', typesTask.dynamicType);
     checkReturn('testSpecialization3', typesTask.intType.nullable());
   }));
 }