Support tasks injection into a running VM.

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index 27a58a49426cad6e81f2b4a620b64129b7959dcb..ba0b0d6232983ed45bff456b3826ff5253688169 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -89,6 +89,7 @@ class ObjectOperationDescriptor;
 class ObjectTemplate;
 class Platform;
 class Primitive;
+class Private;
 class Promise;
 class RawOperationDescriptor;
 class Script;
@@ -99,7 +100,7 @@ class String;
 class StringObject;
 class Symbol;
 class SymbolObject;
-class Private;
+class Task;
 class Uint32;
 class Utils;
 class Value;
@@ -121,7 +122,6 @@ template<typename T> class FunctionCallbackInfo;
 template<typename T> class PropertyCallbackInfo;
 class StackTrace;
 class StackFrame;
-class Isolate;
 class DeclaredAccessorDescriptor;
 class ObjectOperationDescriptor;
 class RawOperationDescriptor;