Change the error handling in dart:io

runtime/bin/file.dart

Index: runtime/bin/file.dart
diff --git a/runtime/bin/file.dart b/runtime/bin/file.dart
index 787e4b8f99f94829494a74b90ebab7b2f1e593c6..963660b7a4ff51b87442cda0594775595fea3a55 100644
--- a/runtime/bin/file.dart
+++ b/runtime/bin/file.dart
@@ -217,7 +217,7 @@ interface File default _File {
    * Sets the handler that gets called when errors occur during
    * operations on this file.
    */
-  void set onError(void handler(Exception e));
+  void set onError(void handler(e));
 }
 
 
@@ -376,7 +376,7 @@ interface RandomAccessFile {
    * Sets the handler that gets called when errors occur when
    * operating on this file.
    */
-  void set onError(void handler(Exception e));
+  void set onError(void handler(e));
 }