Small cleanups to ported QuicServer and dependencies

net/quic/quic_server_bin.cc

Index: net/quic/quic_server_bin.cc
diff --git a/net/quic/quic_server_bin.cc b/net/quic/quic_server_bin.cc
index 63b85a76a71072a26558735dce1bcb73229e7870..1dd45569660d6de0a12d615aca91133238c42d0a 100644
--- a/net/quic/quic_server_bin.cc
+++ b/net/quic/quic_server_bin.cc
@@ -42,9 +42,10 @@ int main(int argc, char *argv[]) {
     exit(0);
   }
 
+  base::FilePath::StringType cache_dir;
   if (line->HasSwitch("quic_in_memory_cache_dir")) {
-    net::g_quic_in_memory_cache_dir =
-        line->GetSwitchValueNative("quic_in_memory_cache_dir");
+    cache_dir = line->GetSwitchValueNative("quic_in_memory_cache_dir");
+    net::g_quic_in_memory_cache_dir = &cache_dir;
   }
 
   if (line->HasSwitch("port")) {