Support 'restart call frame' debug command

src/liveedit.h

Index: src/liveedit.h
diff --git a/src/liveedit.h b/src/liveedit.h
index 424c24e3510831dd18df39fe42946424fcfe9233..a6f3bce69804db98262759778b82b4f968f054fa 100644
--- a/src/liveedit.h
+++ b/src/liveedit.h
@@ -123,6 +123,10 @@ class LiveEdit : AllStatic {
   static Handle<JSArray> CheckAndDropActivations(
       Handle<JSArray> shared_info_array, bool do_drop, Zone* zone);
 
+  // Restarts the callframe and completely drops all frames above it.
+  // Return error message or NULL.
+  static const char* RestartFrame(JavaScriptFrame* frame, Zone* zone);
+
   // A copy of this is in liveedit-debugger.js.
   enum FunctionPatchabilityStatus {
     FUNCTION_AVAILABLE_FOR_PATCH = 1,