Breakpoint position should be inside function body.

src/debug.cc

Index: src/debug.cc
diff --git a/src/debug.cc b/src/debug.cc
index 728813514c4f59095d931a16bcce60a42cc97d17..0957cbcac8436fb8b60f9745bcaa8d261a6216c6 100644
--- a/src/debug.cc
+++ b/src/debug.cc
@@ -170,7 +170,7 @@ void BreakLocationIterator::Next() {
       // Set the positions to the end of the function.
       if (debug_info_->shared()->HasSourceCode()) {
         position_ = debug_info_->shared()->end_position() -
-                    debug_info_->shared()->start_position();
+                    debug_info_->shared()->start_position() - 1;
       } else {
         position_ = 0;
       }