Use metadata annotation @patch for patch classes

runtime/lib/math_patch.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.
 
 import "dart:typed_data";
 
 // A VM patch of the dart:math library.
 
 // If [x] is an [int] and [exponent] is a non-negative [int], the result is
 // an [int], otherwise the result is a [double].
-patch num pow(num x, num exponent) {
+@patch num pow(num x, num exponent) {
   if ((x is int) && (exponent is int) && (exponent >= 0)) {
     return _intPow(x, exponent);
   }
   return _doublePow(x.toDouble(), exponent.toDouble());
 }
 
 double _doublePow(double base, double exponent) {
   if (exponent == 0.0) {
     return 1.0;  // ECMA-262 15.8.2.13
   }
   // Speed up simple cases.
   if (exponent == 1.0) return base;
   if (exponent == 2.0) return base * base;
   if (exponent == 3.0) return base * base * base;
-  
+
   if (base == 1.0) return 1.0;
 
   if (base.isNaN || exponent.isNaN) {
     return double.NAN;
   }
   if ((base != -double.INFINITY) && (exponent == 0.5)) {
     if (base == 0.0) {
       return 0.0;
     }
     return sqrt(base);
@@ skipping 12 matching lines @@
     }
     exponent >>= 1;
     // Skip unnecessary operation (can overflow to Mint or Bigint).
     if (exponent != 0) {
       base *= base;
     }
   }
   return result;
 }
 
-patch double atan2(num a, num b) => _atan2(a.toDouble(), b.toDouble());
-patch double sin(num value) => _sin(value.toDouble());
-patch double cos(num value) => _cos(value.toDouble());
-patch double tan(num value) => _tan(value.toDouble());
-patch double acos(num value) => _acos(value.toDouble());
-patch double asin(num value) => _asin(value.toDouble());
-patch double atan(num value) => _atan(value.toDouble());
-patch double sqrt(num value) => _sqrt(value.toDouble());
-patch double exp(num value) => _exp(value.toDouble());
-patch double log(num value) => _log(value.toDouble());
+@patch double atan2(num a, num b) => _atan2(a.toDouble(), b.toDouble());
+@patch double sin(num value) => _sin(value.toDouble());
+@patch double cos(num value) => _cos(value.toDouble());
+@patch double tan(num value) => _tan(value.toDouble());
+@patch double acos(num value) => _acos(value.toDouble());
+@patch double asin(num value) => _asin(value.toDouble());
+@patch double atan(num value) => _atan(value.toDouble());
+@patch double sqrt(num value) => _sqrt(value.toDouble());
+@patch double exp(num value) => _exp(value.toDouble());
+@patch double log(num value) => _log(value.toDouble());
 
 double _atan2(double a, double b) native "Math_atan2";
 double _sin(double x) native "Math_sin";
 double _cos(double x) native "Math_cos";
 double _tan(double x) native "Math_tan";
 double _acos(double x) native "Math_acos";
 double _asin(double x) native "Math_asin";
 double _atan(double x) native "Math_atan";
 double _sqrt(double x) native "Math_sqrt";
 double _exp(double x) native "Math_exp";
 double _log(double x) native "Math_log";
 
 
 // TODO(iposva): Handle patch methods within a patch class correctly.
-patch class Random {
+@patch class Random {
 
-  /*patch*/ factory Random([int seed]) {
+  /*@patch*/ factory Random([int seed]) {
     var state = _Random._setupSeed((seed == null) ? _Random._nextSeed() : seed);
     // Crank a couple of times to distribute the seed bits a bit further.
     return new _Random._withState(state).._nextState()
                                         .._nextState()
                                         .._nextState()
                                         .._nextState();
   }
 
-  /*patch*/ factory Random.secure() {
+  /*@patch*/ factory Random.secure() {
     return new _SecureRandom();
   }
 }
 
 
 class _Random implements Random {
   // Internal state of the random number generator.
   final _state;
   static const _kSTATE_LO = 0;
   static const _kSTATE_HI = 1;  // Unused in Dart code.
@@ skipping 100 matching lines @@
 
   bool nextBool() {
     return _getBytes(1).isEven;
   }
 
   // Constants used by the algorithm.
   static const _POW2_32 = 1 << 32;
   static const _POW2_53_D = 1.0 * (1 << 53);
 }