Make sure that errors are thrown when there is no error handler

runtime/bin/file_impl.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.
 
 class _FileInputStream extends _BaseDataInputStream implements InputStream {
   _FileInputStream(String name) {
     _file = new File(name);
     _data = [];
     _position = 0;
-    _file.onError = (e) {
-      if (_clientErrorHandler != null) {
-        _clientErrorHandler(e);
-      }
-    };
+    _file.onError = _reportError;
     _file.open(FileMode.READ, (openedFile) {
       _readDataFromFile(openedFile);
     });
   }
 
   _FileInputStream.fromStdio(int fd) {
     assert(fd == 0);
     _file = _File._openStdioSync(fd);
     _data = [];
     _position = 0;
     _readDataFromFile(_file);
   }
 
   void _readDataFromFile(RandomAccessFile openedFile) {
-    openedFile.onError = (e) {
-      if (_clientErrorHandler != null) {
-        _clientErrorHandler(e);
-      }
-    };
+    openedFile.onError = _reportError;
     openedFile.length((length) {
       var contents = new ByteArray(length);
       if (length != 0) {
         openedFile.readList(contents, 0, length, (read) {
           if (read != length) {
-            if (_clientErrorHandler != null) {
-              _clientErrorHandler();
-            }
+            _reportError(new FileIOException(
+                'Failed reading file contents in FileInputStream'));
           } else {
             _data = contents;
           }
           openedFile.close(() {
             _streamMarkedClosed = true;
             _checkScheduleCallbacks();
           });
         });
       } else {
         openedFile.close(() {
@@ skipping 41 matching lines @@
 
 class _FileOutputStream extends _BaseOutputStream implements OutputStream {
   _FileOutputStream(String name, FileMode mode) {
     _pendingOperations = new List<List<int>>();
     var f = new File(name);
     f.open(mode, (openedFile) {
       _file = openedFile;
       _setupFileHandlers();
       _processPendingOperations();
     });
-    f.onError = (e) => _reportError(e);
+    f.onError = _reportError;
   }
 
   _FileOutputStream.fromStdio(int fd) {
     assert(1 <= fd && fd <= 2);
     _file = _File._openStdioSync(fd);
     _setupFileHandlers();
   }
 
 
   void _setupFileHandlers() {
-    _file.onError = (e) => _reportError(e);
+    _file.onError = _reportError;
     _file.onNoPendingWrites = () {
       if (!_streamMarkedClosed && _onNoPendingWrites != null) {
         _onNoPendingWrites();
       }
     };
   }
 
   bool write(List<int> buffer, [bool copyBuffer = false]) {
     var data = buffer;
     if (copyBuffer) {
@@ skipping 166 matching lines @@
     }
     return result;
   }
 
   static int checkedOpen(String name, int mode) {
     if (name is !String || mode is !int) {
       throw new IllegalArgumentException();
     };
     var result = open(name, mode);
     if (result is OSError) {
-      throw new FileIOException("Cannot open file", result);
+      throw new FileIOException("Cannot open file $name", result);
     }
     return result;
   }
 
   static bool checkedCreate(String name) {
     if (name is !String) {
       throw new IllegalArgumentException();
     };
     var result = create(name);
     if (result is OSError) {
@@ skipping 106 matching lines @@
   // Constructor for file.
   _File(String this._name);
 
   void exists(void callback(bool exists)) {
     _ensureFileService();
     List request = new List(2);
     request[0] = _FileUtils.kExistsRequest;
     request[1] = _name;
     _fileService.call(request).then((response) {
       if (_isErrorResponse(response)) {
-        _handleErrorResponse(response, "Cannot open file");
+        _handleErrorResponse(response, "Cannot open file $_name");
       } else {
         callback(response);
       }
     });
   }
 
   bool existsSync() {
     return _FileUtils.checkedExists(_name);
   }
 
@@ skipping 62 matching lines @@
         mode != FileMode.APPEND) {
       _reportError(new IllegalArgumentException());
       return;
     }
     List request = new List(3);
     request[0] = _FileUtils.kOpenRequest;
     request[1] = _name;
     request[2] = mode._mode;  // Direct int value for serialization.
     _fileService.call(request).then((response) {
       if (_isErrorResponse(response)) {
-        _handleErrorResponse(response, "Cannot open file");
+        _handleErrorResponse(response, "Cannot open file $_name");
       } else {
         callback(new _RandomAccessFile(response, _name));
       }
     });
   }
 
   void length(void callback(int length)) {
     _ensureFileService();
     List request = new List(2);
     request[0] = _FileUtils.kLengthFromNameRequest;
@@ skipping 516 matching lines @@
   String _name;
   int _id;
   int _pendingWrites = 0;
 
   SendPort _fileService;
 
   Timer _noPendingWriteTimer;
 
   Function _onNoPendingWrites;
 }