Revert "Unify dart:isolate."

lib/isolate/dart2js/compiler_hooks.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.
+
+// This file contains functions that are used in the code generated by
+// the dart2js compiler.
+
+/**
+ * Wrapper that takes the dart entry point and runs it within an isolate. The
+ * dart2js compiler will inject a call of the form
+ * [: startRootIsolate(main); :] when it determines that this wrapping
+ * is needed. For single-isolate applications (e.g. hello world), this
+ * call is not emitted.
+ */
+void startRootIsolate(entry) {
+  _globalState = new _Manager();
+
+  // Don't start the main loop again, if we are in a worker.
+  if (_globalState.isWorker) return;
+  final rootContext = new _IsolateContext();
+  _globalState.rootContext = rootContext;
+  _fillStatics(rootContext);
+
+  // BUG(5151491): Setting currentContext should not be necessary, but
+  // because closures passed to the DOM as event handlers do not bind their
+  // isolate automatically we try to give them a reasonable context to live in
+  // by having a "default" isolate (the first one created).
+  _globalState.currentContext = rootContext;
+
+  if (_window != null)  {
+    rootContext.eval(() => _setTimerFactoryClosure( _timerFactory));
+  }
+  rootContext.eval(entry);
+  _globalState.topEventLoop.run();
+}