Merge in changes from SDK branch

lib/src/int32.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.
 
 part of fixnum;
 
 /**
  * An immutable 32-bit signed integer, in the range [-2^31, 2^31 - 1].
  * Arithmetic operations may overflow in order to maintain this range.
  */
@@ skipping 39 matching lines @@
       return c - _CC_0;
     } else if (c >= _CC_a && c <= _CC_z) {
       return c - _CC_a + 10;
     } else if (c >= _CC_A && c <= _CC_Z) {
       return c - _CC_A + 10;
     } else {
       return -1; // bad char code
     }
   }
 
+  static int _validateRadix(int radix) {
+    if (2 <= radix && radix <= 36) return radix;
+    throw new RangeError.range(radix, 2, 36, 'radix');
+  }
+
   /**
    * Parses a [String] in a given [radix] between 2 and 16 and returns an
    * [Int32].
    */
   // TODO(rice) - Make this faster by converting several digits at once.
   static Int32 parseRadix(String s, int radix) {
-    if ((radix <= 1) || (radix > 16)) {
-      throw new ArgumentError("Bad radix: $radix");
-    }
+    _validateRadix(radix);
     Int32 x = ZERO;
     for (int i = 0; i < s.length; i++) {
       int c = s.codeUnitAt(i);
       int digit = _decodeDigit(c);
       if (digit < 0 || digit >= radix) {
         throw new FormatException("Non-radix code unit: $c");
       }
       x = (x * radix) + digit;
     }
     return x;
@@ skipping 262 matching lines @@
       if (upperLimit is int) return new Int32(upperLimit);
       throw new ArgumentError(upperLimit);
     }
     return this;
   }
 
   int numberOfLeadingZeros() => _numberOfLeadingZeros(_i);
   int numberOfTrailingZeros() => _numberOfTrailingZeros(_i);
 
   Int32 toSigned(int width) {
-    if (width < 1 || width > 32) throw new ArgumentError(width);
+    if (width < 1 || width > 32) throw new RangeError.range(width, 1, 32);
     return new Int32(_i.toSigned(width));
   }
 
   Int32 toUnsigned(int width) {
-    if (width < 0 || width > 32) throw new ArgumentError(width);
+    if (width < 0 || width > 32) throw new RangeError.range(width, 0, 32);
     return new Int32(_i.toUnsigned(width));
   }
 
   List<int> toBytes() {
     List<int> result = new List<int>(4);
     result[0] = _i & 0xff;
     result[1] = (_i >> 8) & 0xff;
     result[2] = (_i >> 16) & 0xff;
     result[3] = (_i >> 24) & 0xff;
     return result;
   }
 
   double toDouble() => _i.toDouble();
   int toInt() => _i;
   Int32 toInt32() => this;
   Int64 toInt64() => new Int64(_i);
 
   String toString() => _i.toString();
   String toHexString() => _i.toRadixString(16);
   String toRadixString(int radix) => _i.toRadixString(radix);
 }