Don't use variable-length arrays.

Change-Id: I3f70cadaaade189fd834d9aadb8839fe8ad87f1f
diff --git a/src/object_test.cc b/src/object_test.cc
index 3512171..80ed0bb 100644
--- a/src/object_test.cc
+++ b/src/object_test.cc
@@ -35,7 +35,7 @@
                     const char* utf8_in,
                     const char* utf16_expected_le,
                     int32_t expected_hash) {
-    uint16_t utf16_expected[length];
+    UniquePtr<uint16_t[]> utf16_expected(new uint16_t[length]);
     for (int32_t i = 0; i < length; i++) {
       uint16_t ch = (((utf16_expected_le[i*2 + 0] & 0xff) << 8) |
                      ((utf16_expected_le[i*2 + 1] & 0xff) << 0));