Remove some WrapUnique() calls by returing unique_ptrs

testing/libfuzzer/pdf_streamparser_fuzzer.cc

 // Copyright 2016 The PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <cstdint>
+#include <memory>
 
 #include "core/fpdfapi/page/pageint.h"
 #include "core/fpdfapi/parser/cpdf_object.h"
 
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
   CPDF_StreamParser parser(data, size);
-  while (CPDF_Object* pObj = parser.ReadNextObject(true, 0))
-    delete pObj;
+  while (std::unique_ptr<CPDF_Object> pObj = parser.ReadNextObject(true, 0))
+    continue;
 
   return 0;
 }