Simplify and correctify pending message location handling.

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 <queue>
 #include "include/v8-debug.h"
 #include "src/allocation.h"
@@ skipping 268 matching lines @@
   Code* pending_handler_code_;
   intptr_t pending_handler_offset_;
   Address pending_handler_fp_;
   Address pending_handler_sp_;
 
   // Communication channel between Isolate::Throw and message consumers.
   bool has_pending_message_;
   bool rethrowing_message_;
   Object* pending_message_obj_;
   Object* pending_message_script_;
-  int pending_message_start_pos_;
-  int pending_message_end_pos_;
 
   // Use a separate value for scheduled exceptions to preserve the
   // invariants that hold about pending_exception.  We may want to
   // unify them later.
   Object* scheduled_exception_;
   bool external_caught_exception_;
   SaveContext* save_context_;
   v8::TryCatch* catcher_;
 
   // Stack.
@@ skipping 1293 matching lines @@
   }
 
   EmbeddedVector<char, 128> filename_;
   FILE* file_;
   int scope_depth_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ISOLATE_H_