Rationalize coercions

test/dart_codegen/expect/async/async_error.dart

Index: test/dart_codegen/expect/async/async_error.dart
diff --git a/test/dart_codegen/expect/async/async_error.dart b/test/dart_codegen/expect/async/async_error.dart
index 26b2f4e7d4c90c43d40be9e2ecbbf847bdc7d92c..55647d98d0bf44788941271ca7ed26e2babee34c 100644
--- a/test/dart_codegen/expect/async/async_error.dart
+++ b/test/dart_codegen/expect/async/async_error.dart
@@ -12,14 +12,14 @@ part of dart.async;
     return zone.registerBinaryCallback(errorHandler);
     }
    else {
-    return zone.registerUnaryCallback(DEVC$RT.cast(errorHandler, Function, __t0, "CastGeneral", """line 20, column 39 of dart:async/async_error.dart: """, errorHandler is __t0, true));
+    return zone.registerUnaryCallback(DEVC$RT.cast(errorHandler, Function, __t0, "ImplicitCast", """line 20, column 39 of dart:async/async_error.dart: """, errorHandler is __t0, true));
     }
   }
  class _UncaughtAsyncError extends AsyncError {_UncaughtAsyncError(error, StackTrace stackTrace) : super(error, _getBestStackTrace(error, stackTrace));
  static StackTrace _getBestStackTrace(error, StackTrace stackTrace) {
   if (stackTrace != null) return stackTrace;
    if (error is Error) {
-    return DEVC$RT.cast(error.stackTrace, dynamic, StackTrace, "CastGeneral", """line 31, column 14 of dart:async/async_error.dart: """, error.stackTrace is StackTrace, true);
+    return DEVC$RT.cast(error.stackTrace, dynamic, StackTrace, "DynamicCast", """line 31, column 14 of dart:async/async_error.dart: """, error.stackTrace is StackTrace, true);
     }
    return null;
   }