IWYS fixes for //base headers

Tested:
    http://test/OCL:540634127:BASE:540582699:1686874264124:fd0ccf03
    Some test failures are present; the CL author decided to mail
PiperOrigin-RevId: 540962097

quiche/quic/core/http/quic_spdy_session.cc

diff --git a/quiche/quic/core/http/quic_spdy_session.cc b/quiche/quic/core/http/quic_spdy_session.cc
index e764c22..5308158 100644
--- a/quiche/quic/core/http/quic_spdy_session.cc
+++ b/quiche/quic/core/http/quic_spdy_session.cc
@@ -11,6 +11,7 @@
 #include <string>
 #include <utility>
 
+#include "base/casts.h"
 #include "absl/base/attributes.h"
 #include "absl/strings/numbers.h"
 #include "absl/strings/str_cat.h"

quiche/quic/core/http/web_transport_http3.cc

diff --git a/quiche/quic/core/http/web_transport_http3.cc b/quiche/quic/core/http/web_transport_http3.cc
index 6db4eae..acbfc16 100644
--- a/quiche/quic/core/http/web_transport_http3.cc
+++ b/quiche/quic/core/http/web_transport_http3.cc
@@ -7,6 +7,7 @@
 #include <limits>
 #include <memory>
 
+#include "base/casts.h"
 #include "absl/strings/string_view.h"
 #include "absl/types/optional.h"
 #include "quiche/quic/core/http/quic_spdy_session.h"

quiche/quic/tools/quic_spdy_client_base.cc

diff --git a/quiche/quic/tools/quic_spdy_client_base.cc b/quiche/quic/tools/quic_spdy_client_base.cc
index 248e379..6fc5c81 100644
--- a/quiche/quic/tools/quic_spdy_client_base.cc
+++ b/quiche/quic/tools/quic_spdy_client_base.cc
@@ -6,6 +6,7 @@
 
 #include <utility>
 
+#include "base/casts.h"
 #include "absl/strings/numbers.h"
 #include "absl/strings/str_cat.h"
 #include "absl/strings/string_view.h"