Remove QuicString wrapper for std::string

gfe-relnote: n/a (no functional change)
PiperOrigin-RevId: 238124961
Change-Id: I36e66a4326b4118d70effd356aef9734d2893763
diff --git a/quic/core/http/quic_headers_stream_test.cc b/quic/core/http/quic_headers_stream_test.cc
index 7059b72..2f669df 100644
--- a/quic/core/http/quic_headers_stream_test.cc
+++ b/quic/core/http/quic_headers_stream_test.cc
@@ -6,6 +6,7 @@
 
 #include <cstdint>
 #include <ostream>
+#include <string>
 #include <tuple>
 #include <utility>
 #include <vector>
@@ -19,7 +20,6 @@
 #include "net/third_party/quiche/src/quic/platform/api/quic_logging.h"
 #include "net/third_party/quiche/src/quic/platform/api/quic_ptr_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_piece.h"
 #include "net/third_party/quiche/src/quic/platform/api/quic_test.h"
 #include "net/third_party/quiche/src/quic/test_tools/quic_connection_peer.h"