Remove QuicString wrapper for std::string

gfe-relnote: n/a (no functional change)
PiperOrigin-RevId: 238124961
Change-Id: I36e66a4326b4118d70effd356aef9734d2893763
diff --git a/quic/core/quic_connection.cc b/quic/core/quic_connection.cc
index b39f617..0d9a061 100644
--- a/quic/core/quic_connection.cc
+++ b/quic/core/quic_connection.cc
@@ -12,6 +12,7 @@
 #include <limits>
 #include <memory>
 #include <set>
+#include <string>
 #include <utility>
 
 #include "base/macros.h"
@@ -34,7 +35,6 @@
 #include "net/third_party/quiche/src/quic/platform/api/quic_logging.h"
 #include "net/third_party/quiche/src/quic/platform/api/quic_map_util.h"
 #include "net/third_party/quiche/src/quic/platform/api/quic_str_cat.h"
-#include "net/third_party/quiche/src/quic/platform/api/quic_string.h"
 #include "net/third_party/quiche/src/quic/platform/api/quic_string_utils.h"
 #include "net/third_party/quiche/src/quic/platform/api/quic_text_utils.h"