Move network fuzzers from //testing/libfuzzer/fuzzers to //net

net/http/http_chunked_decoder_fuzzer.cc

 // Copyright 2015 The Chromium 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 <stddef.h>
 #include <stdint.h>
 
 #include <vector>
 
 #include "net/http/http_chunked_decoder.h"
 
 // Entry point for LibFuzzer.
 extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
   const char* data_ptr = reinterpret_cast<const char*>(data);
   std::vector<char> buffer(data_ptr, data_ptr + size);
   net::HttpChunkedDecoder decoder;
   decoder.FilterBuf(buffer.data(), buffer.size());
 
   return 0;
 }