Don't throw on 1 ~/ 0.0.

runtime/lib/integers.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.
 
 // TODO(srdjan): fix limitations.
 // - shift amount must be a Smi.
 class IntegerImplementation {
   factory IntegerImplementation._uninstantiable() {
     throw const UnsupportedOperationException(
         "IntegerImplementation can only be allocated by the VM");
   }
   num operator +(num other) {
     return other.addFromInteger(this);
   }
   num operator -(num other) {
     return other.subFromInteger(this);
   }
   num operator *(num other) {
     return other.mulFromInteger(this);
   }
   num operator ~/(num other) {
-    if (other == 0) {
+    if ((other is int) && (other == 0)) {
       throw const IntegerDivisionByZeroException();
     }
     return other.truncDivFromInteger(this);
   }
   num operator /(num other) {
     return this.toDouble() / other.toDouble();
   }
   num operator %(num other) {
     if ((other is int) && (other == 0)) {
       throw const IntegerDivisionByZeroException();
@@ skipping 203 matching lines @@
     }
   }
   int shlFromInt(int other) {
     throw const OutOfMemoryException();
   }
 
   int pow(int exponent) {
     throw "Bigint.pow not implemented";
   }
 }