Don't clear exception pending message if we have externally TryCatch and finally on top of stack.

src/isolate.h

Index: src/isolate.h
diff --git a/src/isolate.h b/src/isolate.h
index bc7646bd4834bafc03bf333f53da14ee072ac451..e33849d01946694484dfde087bc4cc69ee983855 100644
--- a/src/isolate.h
+++ b/src/isolate.h
@@ -605,7 +605,8 @@ class Isolate {
     thread_local_top_.scheduled_exception_ = heap_.the_hole_value();
   }
 
-  bool IsExternallyCaught();
+  bool HasExternalTryCatch();
+  bool IsFinallyOnTop();
 
   bool is_catchable_by_javascript(Object* exception) {
     return exception != heap()->termination_exception();
@@ -1178,7 +1179,10 @@ class Isolate {
 
   void FillCache();
 
-  void PropagatePendingExceptionToExternalTryCatch();
+  // Propagate pending exception message to the v8::TryCatch.
+  // If there is no external try-catch or message was successfully propagated,
+  // then return true.
+  bool PropagatePendingExceptionToExternalTryCatch();
 
   void InitializeDebugger();