[Cronet] Added a unit test in QuicTest to test async API.

components/cronet/android/test/quic_test_server.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 "quic_test_server.h"
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
 #include "base/bind.h"
 #include "base/files/file_path.h"
+#include "base/files/file_util.h"
 #include "base/threading/thread.h"
 #include "jni/QuicTestServer_jni.h"
 #include "net/base/ip_endpoint.h"
 #include "net/base/net_util.h"
 #include "net/tools/quic/quic_in_memory_cache.h"
 #include "net/tools/quic/quic_simple_server.h"
 
 namespace cronet {
 
 namespace {
 
 static const char kServerHost[] = "127.0.0.1";
 static const int kServerPort = 6121;
 
 base::Thread* g_quic_server_thread = nullptr;
 net::tools::QuicSimpleServer* g_quic_server = nullptr;
 
 void ServeFilesFromDirectory(
     const base::FilePath& directory) {
   DCHECK(g_quic_server_thread->task_runner()->BelongsToCurrentThread());
   DCHECK(!g_quic_server);
   base::FilePath file_dir = directory.Append("quic_data");
+  bool file_exist = base::PathExists(file_dir);
+  CHECK(file_exist) << "Quic data does not exist";

[mef, 2015/05/13 17:00:03]

Do we need |file_exist| variable?

[xunjieli, 2015/05/13 17:06:16]

Done. I don't think we do.

   net::tools::QuicInMemoryCache::GetInstance()->InitializeFromDirectory(
       file_dir.value());
   net::IPAddressNumber ip;
   net::ParseIPLiteralToNumber(kServerHost, &ip);
   net::QuicConfig config;
   g_quic_server =
       new net::tools::QuicSimpleServer(config, net::QuicSupportedVersions());
   int rv = g_quic_server->Listen(net::IPEndPoint(ip, kServerPort));
   CHECK_GE(rv, 0) << "Quic server fails to start";
   JNIEnv* env = base::android::AttachCurrentThread();
@@ skipping 38 matching lines @@
 
 int GetServerPort(JNIEnv* env, jclass /*jcaller*/) {
   return kServerPort;
 }
 
 bool RegisterQuicTestServer(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace cronet