Use thread_local for storing ThreadId

Change-Id: Ifc754fb81089aed4cb79b1f6c4aab0cb73a2a5d7
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2537690
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71176}

src/base/platform/platform.h

@@ -385,13 +385,7 @@ class V8_BASE_EXPORT Thread {
   static LocalStorageKey CreateThreadLocalKey();
   static void DeleteThreadLocalKey(LocalStorageKey key);
   static void* GetThreadLocal(LocalStorageKey key);
-  static int GetThreadLocalInt(LocalStorageKey key) {
-    return static_cast<int>(reinterpret_cast<intptr_t>(GetThreadLocal(key)));
-  }
   static void SetThreadLocal(LocalStorageKey key, void* value);
-  static void SetThreadLocalInt(LocalStorageKey key, int value) {
-    SetThreadLocal(key, reinterpret_cast<void*>(static_cast<intptr_t>(value)));
-  }
   static bool HasThreadLocal(LocalStorageKey key) {
     return GetThreadLocal(key) != nullptr;
   }

src/execution/thread-id.cc

@@ -11,27 +11,22 @@ namespace internal {
 
 namespace {
 
-DEFINE_LAZY_LEAKY_OBJECT_GETTER(base::Thread::LocalStorageKey, GetThreadIdKey,
-                                base::Thread::CreateThreadLocalKey())
+thread_local int thread_id = 0;
 
 std::atomic<int> next_thread_id{1};
 
 }  // namespace
 
 // static
 ThreadId ThreadId::TryGetCurrent() {
-  int thread_id = base::Thread::GetThreadLocalInt(*GetThreadIdKey());
   return thread_id == 0 ? Invalid() : ThreadId(thread_id);
 }
 
 // static
 int ThreadId::GetCurrentThreadId() {
-  auto key = *GetThreadIdKey();
-  int thread_id = base::Thread::GetThreadLocalInt(key);
   if (thread_id == 0) {
     thread_id = next_thread_id.fetch_add(1);
     CHECK_LE(1, thread_id);
-    base::Thread::SetThreadLocalInt(key, thread_id);
   }
   return thread_id;
 }