Rename 'dart:debugger' to 'dart:developer'

runtime/lib/debugger.dart

Index: runtime/lib/debugger.dart
diff --git a/runtime/lib/debugger.dart b/runtime/lib/debugger.dart
deleted file mode 100644
index 8e381cad1602a32f67e2fb1d4738dcb8489423b6..0000000000000000000000000000000000000000
--- a/runtime/lib/debugger.dart
+++ /dev/null
@@ -1,10 +0,0 @@
-// Copyright (c) 2015, 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.
-
-import 'dart:_internal';
-
-patch class Debugger {
-  /* patch */ static void breakHere() native "Debugger_breakHere";
-  /* patch */ static void breakHereIf(bool expr) native "Debugger_breakHereIf";
-}