handle the special snowflakes that are Integer Indexed Exotic objects

src/runtime/runtime-debug.cc

Index: src/runtime/runtime-debug.cc
diff --git a/src/runtime/runtime-debug.cc b/src/runtime/runtime-debug.cc
index 180f0137d1bf7d0a21e2296660719adb77eeb9e8..935399e4330e842b3d05569634b2f7bf6121e916 100644
--- a/src/runtime/runtime-debug.cc
+++ b/src/runtime/runtime-debug.cc
@@ -72,6 +72,7 @@ static Handle<Object> DebugGetProperty(LookupIterator* it,
       case LookupIterator::ACCESS_CHECK:
         // Ignore access checks.
         break;
+      case LookupIterator::INTEGER_INDEXED_EXOTIC:
       case LookupIterator::INTERCEPTOR:
       case LookupIterator::JSPROXY:
         return it->isolate()->factory()->undefined_value();