Breakpoint position should be inside function body.

test/mjsunit/debug-return-value.js

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 83 matching lines @@
               assertEquals(debugger_source_position + 38,
                            exec_state.frame(0).sourcePosition());
             }
             break;
           default:
             fail("Unexpected");
         }
         exec_state.prepareStep(Debug.StepAction.StepIn, 1);
       } else {
         // Position at the end of the function.
-        assertEquals(debugger_source_position + 51,
+        assertEquals(debugger_source_position + 50,
         exec_state.frame(0).sourcePosition());
         
         // Just about to return from the function.
         assertTrue(exec_state.frame(0).isAtReturn())
         assertEquals(expected_return_value,
                      exec_state.frame(0).returnValue().value());
         
         // Check the same using the JSON commands.
         var dcp = exec_state.debugCommandProcessor(false);
         var request = '{"seq":0,"type":"request","command":"backtrace"}';
@@ skipping 39 matching lines @@
 assertTrue(listener_complete);
 assertEquals(4, break_count);
 
 break_count = 0;
 expected_return_value = 2;
 listener_complete = false;
 f(false);
 assertFalse(exception, "exception in listener")
 assertTrue(listener_complete);
 assertEquals(4, break_count);