Support tasks injection into a running VM.

include/v8-debug.h

Index: include/v8-debug.h
diff --git a/include/v8-debug.h b/include/v8-debug.h
index 6abf4e095bccadacdb6ef3fa4a3fc06fcbc76966..9be5c2d49002d65d4463fd1d9ec7f3aa122c90d2 100644
--- a/include/v8-debug.h
+++ b/include/v8-debug.h
@@ -177,6 +177,17 @@ class V8_EXPORT Debug {
   // stops.
   static void DebugBreakForCommand(Isolate* isolate, ClientData* data);
 
+  class Task {

[Sven Panne, 2014/12/18 08:27:50]

We already have v8::Task, why do we need another one?

In general, it's a pity that we can't use std::function yet.

[alph, 2014/12/18 14:28:03]

Sorry, missed the v8::Task.

+   public:
+    virtual void Run() = 0;
+    virtual ~Task() {}
+  };
+
+  // Break execution of JavaScript in the given isolate (this method
+  // can be invoked from a non-VM thread) and execute the given task on the
+  // VM thread. The VM takes ownership of the task.

[Sven Panne, 2014/12/18 08:27:51]

Please extend the comment a bit, describing that the task is run at most once
and deleted after that. Another thing which needs a description: If it is not
run, when exactly does it get destroyed?

[alph, 2014/12/18 14:28:03]

Done.

+  static void BreakAndRun(Isolate* isolate, Task* task);
+
   // Message based interface. The message protocol is JSON.
   static void SetMessageHandler(MessageHandler handler);