[test] Move cctest/test-threads to unittests/execution/

... threads-unittest.

Bug: v8:12781
Change-Id: I1294d0bf9f47c158532a489657bc1e5349afce79
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3682882Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: 王澳 <wangao.james@bytedance.com>
Cr-Commit-Position: refs/heads/main@{#80881}

test/cctest/BUILD.gn

@@ -230,7 +230,6 @@ v8_source_set("cctest_sources") {
     "test-swiss-name-dictionary.cc",
     "test-temporal-parser.cc",
     "test-thread-termination.cc",
-    "test-threads.cc",
     "test-trace-event.cc",
     "test-transitions.cc",
     "test-transitions.h",

test/unittests/BUILD.gn

@@ -333,6 +333,7 @@ v8_source_set("unittests_sources") {
     "diagnostics/eh-frame-writer-unittest.cc",
     "diagnostics/gdb-jit-unittest.cc",
     "execution/microtask-queue-unittest.cc",
+    "execution/threads-unittest.cc",
     "gay-fixed.cc",
     "gay-fixed.h",
     "gay-precision.cc",

test/cctest/test-threads.cc → test/unittests/execution/threads-unittest.cc

@@ -25,13 +25,15 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#include "test/cctest/cctest.h"
-
 #include "src/execution/thread-id.h"
+#include "test/unittests/test-utils.h"
+#include "testing/gtest/include/gtest/gtest.h"
 
 namespace v8 {
 namespace internal {
 
+using ThreadsTest = TestWithIsolate;
+
 // {ThreadId} must be trivially copyable to be stored in {std::atomic}.
 ASSERT_TRIVIALLY_COPYABLE(i::ThreadId);
 using AtomicThreadId = std::atomic<i::ThreadId>;
@@ -66,7 +68,7 @@ class ThreadIdValidationThread : public base::Thread {
   base::Semaphore* const semaphore_;
 };
 
-TEST(ThreadIdValidation) {
+TEST_F(ThreadsTest, ThreadIdValidation) {
   constexpr int kNThreads = 100;
   std::unique_ptr<ThreadIdValidationThread> threads[kNThreads];
   AtomicThreadId refs[kNThreads];