QUIC - (no behavior change) s/NULL/nullptr/g in .../quic/...

net/quic/quic_in_memory_cache.cc

Index: net/quic/quic_in_memory_cache.cc
diff --git a/net/quic/quic_in_memory_cache.cc b/net/quic/quic_in_memory_cache.cc
index 58c6e90f89cd6c1a77f6feb6bc299b9ed8a842ba..31e346f6b5d93d850f13d8353373394df1e221f6 100644
--- a/net/quic/quic_in_memory_cache.cc
+++ b/net/quic/quic_in_memory_cache.cc
@@ -38,7 +38,7 @@ const QuicInMemoryCache::Response* QuicInMemoryCache::GetResponse(
     const GURL& url) const {
   ResponseMap::const_iterator it = responses_.find(GetKey(url));
   if (it == responses_.end()) {
-    return NULL;
+    return nullptr;
   }
   return it->second;
 }
@@ -83,7 +83,7 @@ void QuicInMemoryCache::AddSpecialResponse(StringPiece path,
                                            SpecialResponseType response_type) {
   GURL url("http://" + path.as_string());
 
-  AddResponse(url, NULL, string());
+  AddResponse(url, nullptr, string());
   responses_[GetKey(url)]->response_type_ = response_type;
 }