Move parseInt parseDouble to int/double classes as a static method.

pkg/fixnum/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.
 
 /**
  * An immutable 32-bit signed integer, in the range [-2^31, 2^31 - 1].
  * Arithmetic operations may overflow in order to maintain this range.
  */
 class int32 implements intx {
 
@@ skipping 61 matching lines @@
         throw new Exception("Non-radix char code: $c");
       }
       x = (x * radix) + digit;
     }
     return x;
   }
 
   /**
    * Parses a decimal [String] and returns an [int32].
    */
-  static int32 parseInt(String s) => new int32.fromInt(Math.parseInt(s));
+  static int32 parseInt(String s) => new int32.fromInt(int.parse(s));
 
   /**
    * Parses a hexadecimal [String] and returns an [int32].
    */
   static int32 parseHex(String s) => parseRadix(s, 16);
 
   // Assumes i is <= 32-bit.
   static int _bitCount(int i) {
     // See "Hacker's Delight", section 5-1, "Counting 1-Bits".
 
@@ skipping 252 matching lines @@
   }
 
   int toInt() => _i;
   int32 toInt32() => this;
   int64 toInt64() => new int64.fromInt(_i);
 
   String toString() => _i.toString();
   String toHexString() => _i.toRadixString(16);
   String toRadixString(int radix) => _i.toRadixString(radix);
 }