cleanup patch generation to preseve comments and remove @patch

test/generated_sdk/lib/core/stopwatch.dart

Index: test/generated_sdk/lib/core/stopwatch.dart
diff --git a/test/generated_sdk/lib/core/stopwatch.dart b/test/generated_sdk/lib/core/stopwatch.dart
index ac276809917bd8a9426434929db4497cb58abddb..1307eb1118fc72011433ee383a0f05649d155dd2 100644
--- a/test/generated_sdk/lib/core/stopwatch.dart
+++ b/test/generated_sdk/lib/core/stopwatch.dart
@@ -134,11 +134,13 @@ class Stopwatch {
    */
   static int _frequency;
 
-  @patch
+  /**
+   * Initializes the time-measuring system. *Must* initialize the [_frequency]
+   * variable.
+   */
   static void _initTicker() {
     Primitives.initTicker();
     _frequency = Primitives.timerFrequency;
   }
-  @patch
   static int _now() => Primitives.timerTicks();
 }