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

src/isolate.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_ISOLATE_H_
 #define V8_ISOLATE_H_
 
 #include "include/v8-debug.h"
 #include "src/allocation.h"
 #include "src/assert-scope.h"
@@ skipping 586 matching lines @@
   }
   bool has_scheduled_exception() {
     ASSERT(!thread_local_top_.scheduled_exception_->IsException());
     return thread_local_top_.scheduled_exception_ != heap_.the_hole_value();
   }
   void clear_scheduled_exception() {
     ASSERT(!thread_local_top_.scheduled_exception_->IsException());
     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();
   }
 
   // Serializer.
   void PushToPartialSnapshotCache(Object* obj);
 
   // JS execution stack (see frames.h).
   static Address c_entry_fp(ThreadLocalTop* thread) {
@@ skipping 554 matching lines @@
 
   void InitializeThreadLocal();
 
   void MarkCompactPrologue(bool is_compacting,
                            ThreadLocalTop* archived_thread_data);
   void MarkCompactEpilogue(bool is_compacting,
                            ThreadLocalTop* archived_thread_data);
 
   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();
 
   // Traverse prototype chain to find out whether the object is derived from
   // the Error object.
   bool IsErrorObject(Handle<Object> obj);
 
   base::Atomic32 id_;
   EntryStackItem* entry_stack_;
   int stack_trace_nesting_level_;
   StringStream* incomplete_message_;
   Address isolate_addresses_[kIsolateAddressCount + 1];  // NOLINT
@@ skipping 296 matching lines @@
   }
 
   EmbeddedVector<char, 128> filename_;
   FILE* file_;
   int scope_depth_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ISOLATE_H_