Revert 22380 to investigate windows build break.

runtime/vm/isolate.h

 // Copyright (c) 2013, 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.
 
 #ifndef VM_ISOLATE_H_
 #define VM_ISOLATE_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/thread.h"
@@ skipping 363 matching lines @@
   }
 
   static void SetShutdownCallback(Dart_IsolateShutdownCallback cb) {
     shutdown_callback_ = cb;
   }
   static Dart_IsolateShutdownCallback ShutdownCallback() {
     return shutdown_callback_;
   }
 
   static void SetFileCallbacks(Dart_FileOpenCallback file_open,
-                               Dart_FileReadCallback file_read,
                                Dart_FileWriteCallback file_write,
                                Dart_FileCloseCallback file_close) {
     file_open_callback_ = file_open;
-    file_read_callback_ = file_read;
     file_write_callback_ = file_write;
     file_close_callback_ = file_close;
   }
 
   static Dart_FileOpenCallback file_open_callback() {
     return file_open_callback_;
   }
-  static Dart_FileReadCallback file_read_callback() {
-    return file_read_callback_;
-  }
   static Dart_FileWriteCallback file_write_callback() {
     return file_write_callback_;
   }
   static Dart_FileCloseCallback file_close_callback() {
     return file_close_callback_;
   }
 
   intptr_t* deopt_cpu_registers_copy() const {
     return deopt_cpu_registers_copy_;
   }
@@ skipping 109 matching lines @@
 
   // Status support.
   char* stacktrace_;
   intptr_t stack_frame_index_;
 
   static Dart_IsolateCreateCallback create_callback_;
   static Dart_IsolateInterruptCallback interrupt_callback_;
   static Dart_IsolateUnhandledExceptionCallback unhandled_exception_callback_;
   static Dart_IsolateShutdownCallback shutdown_callback_;
   static Dart_FileOpenCallback file_open_callback_;
-  static Dart_FileReadCallback file_read_callback_;
   static Dart_FileWriteCallback file_write_callback_;
   static Dart_FileCloseCallback file_close_callback_;
   static Dart_IsolateInterruptCallback vmstats_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(Isolate);
 };
 
 // When we need to execute code in an isolate, we use the
 // StartIsolateScope.
 class StartIsolateScope {
@@ skipping 102 matching lines @@
 
  private:
   Isolate::IsolateRunState saved_state_;
 
   DISALLOW_COPY_AND_ASSIGN(IsolateRunStateManager);
 };
 
 }  // namespace dart
 
 #endif  // VM_ISOLATE_H_