Make ~/, round, ceil, floor, truncate return ints. Remove toInt.

samples/third_party/dromaeo/common/BenchUtil.dart

Index: samples/third_party/dromaeo/common/BenchUtil.dart
diff --git a/samples/third_party/dromaeo/common/BenchUtil.dart b/samples/third_party/dromaeo/common/BenchUtil.dart
index 2d0a487bf63e9f539f78f97782968ada6eab0456..1bc419ee0a99f6ffcb420f2cdc8cfc7012c7bd9c 100644
--- a/samples/third_party/dromaeo/common/BenchUtil.dart
+++ b/samples/third_party/dromaeo/common/BenchUtil.dart
@@ -23,7 +23,7 @@ class BenchUtil {
   static void shuffle(List<Object> list) {
     int len = list.length - 1;
     for (int i = 0; i < len; i++) {
-      int index = (Math.random() * (len - i)).toInt() + i;
+      int index = (Math.random() * (len - i)).truncate() + i;
       Object tmp = list[i];
       list[i] = list[index];
       list[index] = tmp;