Minor cleanup: IWYU, clang-tidy, etc.

PiperOrigin-RevId: 618297183

src/google/protobuf/BUILD.bazel

@@ -333,6 +333,7 @@ cc_library(
     deps = [
         "//src/google/protobuf:port",
         "//src/google/protobuf/stubs:lite",
+        "@com_google_absl//absl/base:core_headers",
         "@com_google_absl//absl/log:absl_check",
         "@com_google_absl//absl/log:absl_log",
         "@com_google_absl//absl/numeric:bits",

src/google/protobuf/arena_align.h

@@ -55,6 +55,7 @@
 #include <cstddef>
 #include <cstdint>
 
+#include "google/protobuf/stubs/common.h"
 #include "absl/log/absl_check.h"
 #include "absl/numeric/bits.h"
 

src/google/protobuf/thread_safe_arena.h

@@ -10,16 +10,16 @@
 #ifndef GOOGLE_PROTOBUF_THREAD_SAFE_ARENA_H__
 #define GOOGLE_PROTOBUF_THREAD_SAFE_ARENA_H__
 
-#include <algorithm>
 #include <atomic>
-#include <string>
+#include <cstddef>
+#include <cstdint>
 #include <type_traits>
-#include <utility>
+#include <vector>
 
+#include "absl/base/attributes.h"
 #include "absl/synchronization/mutex.h"
 #include "google/protobuf/arena_align.h"
 #include "google/protobuf/arena_allocation_policy.h"
-#include "google/protobuf/arena_cleanup.h"
 #include "google/protobuf/arenaz_sampler.h"
 #include "google/protobuf/port.h"
 #include "google/protobuf/serial_arena.h"