Pass QuicInMemoryCache directly instead of using a singleton.

net/tools/quic/quic_simple_server_bin.cc

Index: net/tools/quic/quic_simple_server_bin.cc
diff --git a/net/tools/quic/quic_simple_server_bin.cc b/net/tools/quic/quic_simple_server_bin.cc
index abcea6d755ea4a2a861b37f6c9a8b92ed592ff5e..e8f0c9205c038fe2f7c876a870c9dec1c59ba398 100644
--- a/net/tools/quic/quic_simple_server_bin.cc
+++ b/net/tools/quic/quic_simple_server_bin.cc
@@ -57,8 +57,9 @@ int main(int argc, char* argv[]) {
     exit(0);
   }
 
+  net::QuicInMemoryCache in_memory_cache;
   if (line->HasSwitch("quic_in_memory_cache_dir")) {
-    net::QuicInMemoryCache::GetInstance()->InitializeFromDirectory(
+    in_memory_cache.InitializeFromDirectory(
         line->GetSwitchValueASCII("quic_in_memory_cache_dir"));
   }
 
@@ -86,7 +87,7 @@ int main(int argc, char* argv[]) {
       CreateProofSource(line->GetSwitchValuePath("certificate_file"),
                         line->GetSwitchValuePath("key_file")),
       config, net::QuicCryptoServerConfig::ConfigOptions(),
-      net::AllSupportedVersions());
+      net::AllSupportedVersions(), &in_memory_cache);
 
   int rc = server.Listen(net::IPEndPoint(ip, FLAGS_port));
   if (rc < 0) {