unfork DDC's copy of most SDK libraries

pkg/dev_compiler/tool/input_sdk/private/isolate_helper.dart

Index: pkg/dev_compiler/tool/input_sdk/private/isolate_helper.dart
diff --git a/pkg/dev_compiler/tool/input_sdk/private/isolate_helper.dart b/pkg/dev_compiler/tool/input_sdk/private/isolate_helper.dart
index 975dde740e228a69fa7b3179d31bd02e5f135525..a6310d5d8316d43e3a185d0825144f3562a03c04 100644
--- a/pkg/dev_compiler/tool/input_sdk/private/isolate_helper.dart
+++ b/pkg/dev_compiler/tool/input_sdk/private/isolate_helper.dart
@@ -382,10 +382,6 @@ class _IsolateContext implements IsolateContext {
       return;
     }
     void respond() { responsePort.send(null); }
-    if (pingType == Isolate.AS_EVENT) {
-      _globalState.topEventLoop.enqueue(this, respond, "ping");
-      return;
-    }
     assert(pingType == Isolate.BEFORE_NEXT_EVENT);
     if (_scheduledControlEvents == null) {
       _scheduledControlEvents = new Queue();
@@ -401,10 +397,6 @@ class _IsolateContext implements IsolateContext {
       kill();
       return;
     }
-    if (priority == Isolate.AS_EVENT) {
-      _globalState.topEventLoop.enqueue(this, kill, "kill");
-      return;
-    }
     assert(priority == Isolate.BEFORE_NEXT_EVENT);
     if (_scheduledControlEvents == null) {
       _scheduledControlEvents = new Queue();