Sane asynchronous debugging and stack traces

runtime/vm/service/service.md

Index: runtime/vm/service/service.md
diff --git a/runtime/vm/service/service.md b/runtime/vm/service/service.md
index 1c9bb72a4bc2975ac38b2db60b1274940234481e..af036e810717c535b959dc05c3c4011054648fcc 100644
--- a/runtime/vm/service/service.md
+++ b/runtime/vm/service/service.md
@@ -1486,6 +1486,26 @@ A _FlagList_ represents the complete set of VM command line flags.
 ### Frame
 
 ```
+enum AsyncFrameKind {
+  LiveFrame,
+  MarkerFrame,
+  HistoricalFrame,
+}
+```
+
+```
+class AsyncFrame extends Response {
+  AsyncFrameKind kind;
+  int index;
+  @Function function [optional];
+  @Code code [optional];
+  SourceLocation location [optional];
+  BoundVariable[] vars [optional];
+  String marker [optional];
+}
+```
+
+```
 class Frame extends Response {
   int index;
   @Function function;
@@ -2417,6 +2437,7 @@ and therefore will not contain a _type_ property.
 ```
 class Stack extends Response {
   Frame[] frames;
+  AsyncFrame[] asyncFrames [optional];
   Message[] messages;
 }
 ```