Add special rules in the inferrer that some int operations return an int.

tests/compiler/dart2js/simple_inferrer_test.dart

Index: tests/compiler/dart2js/simple_inferrer_test.dart
===================================================================
--- tests/compiler/dart2js/simple_inferrer_test.dart	(revision 21800)
+++ tests/compiler/dart2js/simple_inferrer_test.dart	(working copy)
@@ -41,12 +41,12 @@
   return a++;
 }
 
-returnNum3() {
+returnInt5() {
   var a = 42;
   return ++a;
 }
 
-returnNum4() {
+returnInt6() {
   var a = 42;
   a++;
   return a;
@@ -65,6 +65,24 @@
   return (42);
 }
 
+returnInt7() {
+  return 42.abs();
+}
+
+returnInt8() {
+  return 42.remainder(54);
+}
+
+returnDynamic1() {
+  // Ensure that we don't intrisify a wrong call to [int.remainder].
+  return 42.remainder();
+}
+
+returnDynamic2() {
+  // Ensure that we don't intrisify a wrong call to [int.abs].
+  return 42.abs(42);
+}
+
 get topLevelGetter => 42;
 returnDynamic() => topLevelGetter(42);
 
@@ -75,26 +93,26 @@
 
   get myField => 42;
   set myField(a) {}
-  returnNum1() => ++myField;
-  returnNum2() => ++this.myField;
-  returnNum3() => this.myField += 42;
-  returnNum4() => myField += 42;
+  returnInt1() => ++myField;
+  returnInt2() => ++this.myField;
+  returnInt3() => this.myField += 42;
+  returnInt4() => myField += 42;
   operator[](index) => 42;
   operator[]= (index, value) {}
-  returnNum5() => ++this[0];
-  returnNum6() => this[0] += 1;
+  returnInt5() => ++this[0];
+  returnInt6() => this[0] += 1;
 }
 
 class B extends A {
   B() : super.generative();
-  returnNum1() => ++new A().myField;
-  returnNum2() => new A().myField += 4;
-  returnNum3() => ++new A()[0];
-  returnNum4() => new A()[0] += 42;
-  returnNum5() => ++super.myField;
-  returnNum6() => super.myField += 4;
-  returnNum7() => ++super[0];
-  returnNum8() => super[0] += 54;
+  returnInt1() => ++new A().myField;
+  returnInt2() => new A().myField += 4;
+  returnInt3() => ++new A()[0];
+  returnInt4() => new A()[0] += 42;
+  returnInt5() => ++super.myField;
+  returnInt6() => super.myField += 4;
+  returnInt7() => ++super[0];
+  returnInt8() => super[0] += 54;
 }
 
 main() {
@@ -106,26 +124,30 @@
   returnInt4();
   returnDouble(true);
   returnGiveUp(true);
-  returnNum3();
-  returnNum4();
+  returnInt5();
+  returnInt6();
+  returnInt7();
+  returnInt8();
   returnIntOrNull(true);
   returnDynamic();
+  returnDynamic1();
+  returnDynamic2();
   new A() == null;
-  new A()..returnNum1()
-         ..returnNum2()
-         ..returnNum3()
-         ..returnNum4()
-         ..returnNum5()
-         ..returnNum6();
+  new A()..returnInt1()
+         ..returnInt2()
+         ..returnInt3()
+         ..returnInt4()
+         ..returnInt5()
+         ..returnInt6();
 
-  new B()..returnNum1()
-         ..returnNum2()
-         ..returnNum3()
-         ..returnNum4()
-         ..returnNum5()
-         ..returnNum6()
-         ..returnNum7()
-         ..returnNum8();
+  new B()..returnInt1()
+         ..returnInt2()
+         ..returnInt3()
+         ..returnInt4()
+         ..returnInt5()
+         ..returnInt6()
+         ..returnInt7()
+         ..returnInt8();
 }
 """;
 
@@ -148,12 +170,16 @@
   checkReturn('returnInt2', typesInferrer.intType);
   checkReturn('returnDouble', typesInferrer.doubleType);
   checkReturn('returnGiveUp', interceptorType);
-  checkReturn('returnNum3', typesInferrer.numType);
-  checkReturn('returnNum4', typesInferrer.numType);
+  checkReturn('returnInt5', typesInferrer.intType);
+  checkReturn('returnInt6', typesInferrer.intType);
   checkReturn('returnIntOrNull', typesInferrer.intType.nullable());
   checkReturn('returnInt3', typesInferrer.intType);
   checkReturn('returnDynamic', typesInferrer.dynamicType);
   checkReturn('returnInt4', typesInferrer.intType);
+  checkReturn('returnInt7', typesInferrer.intType);
+  checkReturn('returnInt8', typesInferrer.intType);
+  checkReturn('returnDynamic1', typesInferrer.dynamicType);
+  checkReturn('returnDynamic2', typesInferrer.dynamicType);
 
   checkReturnInClass(String className, String methodName, type) {
     var cls = findElement(compiler, className);
@@ -161,22 +187,22 @@
     Expect.equals(type, typesInferrer.internal.returnTypeOf[element]);
   }
 
-  checkReturnInClass('A', 'returnNum1', typesInferrer.numType);
-  checkReturnInClass('A', 'returnNum2', typesInferrer.numType);
-  checkReturnInClass('A', 'returnNum3', typesInferrer.numType);
-  checkReturnInClass('A', 'returnNum4', typesInferrer.numType);
-  checkReturnInClass('A', 'returnNum5', typesInferrer.numType);
-  checkReturnInClass('A', 'returnNum6', typesInferrer.numType);
+  checkReturnInClass('A', 'returnInt1', typesInferrer.intType);
+  checkReturnInClass('A', 'returnInt2', typesInferrer.intType);
+  checkReturnInClass('A', 'returnInt3', typesInferrer.intType);
+  checkReturnInClass('A', 'returnInt4', typesInferrer.intType);
+  checkReturnInClass('A', 'returnInt5', typesInferrer.intType);
+  checkReturnInClass('A', 'returnInt6', typesInferrer.intType);
   checkReturnInClass('A', '==', interceptorType);
 
-  checkReturnInClass('B', 'returnNum1', typesInferrer.numType);
-  checkReturnInClass('B', 'returnNum2', typesInferrer.numType);
-  checkReturnInClass('B', 'returnNum3', typesInferrer.numType);
-  checkReturnInClass('B', 'returnNum4', typesInferrer.numType);
-  checkReturnInClass('B', 'returnNum5', typesInferrer.numType);
-  checkReturnInClass('B', 'returnNum6', typesInferrer.numType);
-  checkReturnInClass('B', 'returnNum7', typesInferrer.numType);
-  checkReturnInClass('B', 'returnNum8', typesInferrer.numType);
+  checkReturnInClass('B', 'returnInt1', typesInferrer.intType);
+  checkReturnInClass('B', 'returnInt2', typesInferrer.intType);
+  checkReturnInClass('B', 'returnInt3', typesInferrer.intType);
+  checkReturnInClass('B', 'returnInt4', typesInferrer.intType);
+  checkReturnInClass('B', 'returnInt5', typesInferrer.intType);
+  checkReturnInClass('B', 'returnInt6', typesInferrer.intType);
+  checkReturnInClass('B', 'returnInt7', typesInferrer.intType);
+  checkReturnInClass('B', 'returnInt8', typesInferrer.intType);
 
   checkFactoryConstructor(String className) {
     var cls = findElement(compiler, className);