Rename fletch -> dartino

src/pkg/power_management/power_management_extension_linux.cc

 // Copyright (c) 2015, the Dartino 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.md file.
 
-#if defined(FLETCH_TARGET_OS_LINUX)
+#if defined(DARTINO_TARGET_OS_LINUX)
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include "include/dart_api.h"
 #include "include/dart_native_api.h"
 
 #include "power_management_extension.h"
 
 // Dummy implementation for Linux.
 int64_t HandleDisableSleep(const char* reason) {
   // Currently not implemented on Linux.
   return 0;
 }
 
 // Dummy implementation for Linux.
 void HandleEnableSleep(int64_t disable_id) {
   // Currently not implemented on Linux.
 }
 
-#endif  // FLETCH_TARGET_OS_LINUX
+#endif  // DARTINO_TARGET_OS_LINUX