Fix test OneByteArrayJoin.

test/cctest/test-strings.cc

Index: test/cctest/test-strings.cc
diff --git a/test/cctest/test-strings.cc b/test/cctest/test-strings.cc
index 49e9f2870c2cedee157ffc975a14807a4f950aae..7fe0287fbd1d7df8d1568a3e99946d51ae22ec7f 100644
--- a/test/cctest/test-strings.cc
+++ b/test/cctest/test-strings.cc
@@ -1301,7 +1301,7 @@ UNINITIALIZED_TEST(OneByteArrayJoin) {
   v8::Isolate::CreateParams create_params;
   // Set heap limits.
   create_params.constraints.set_max_semi_space_size(1);
-  create_params.constraints.set_max_old_space_size(6);
+  create_params.constraints.set_max_old_space_size(7);
   create_params.array_buffer_allocator = CcTest::array_buffer_allocator();
   v8::Isolate* isolate = v8::Isolate::New(create_params);
   isolate->Enter();