(not for review): PlatformThreadHandle: remove public id() interface

base/threading/thread_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/threading/thread.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/location.h"
@@ skipping 176 matching lines @@
   EXPECT_FALSE(a.message_loop());
   EXPECT_FALSE(a.IsRunning());
 }
 
 TEST_F(ThreadTest, ThreadName) {
   Thread a("ThreadName");
   EXPECT_TRUE(a.Start());
   EXPECT_EQ("ThreadName", a.thread_name());
 }
 
+TEST_F(ThreadTest, ThreadId) {
+  Thread a("ThreadId0");
+  Thread b("ThreadId1");
+  a.Start();
+  b.Start();
+
+  // A started thread should have a valid ID.
+  EXPECT_NE(base::kInvalidThreadId, a.thread_id());
+  EXPECT_NE(base::kInvalidThreadId, b.thread_id());
+
+  // Each thread should have a different thread ID.
+  EXPECT_NE(a.thread_id(), b.thread_id());
+}
+
+TEST_F(ThreadTest, ThreadIdWithRestart) {
+  Thread a("ThreadIdWithRestart");
+  base::PlatformThreadId previous_id = base::kInvalidThreadId;
+
+  for (size_t i = 0; i < 16; ++i) {
+    EXPECT_TRUE(a.Start());
+    base::PlatformThreadId current_id = a.thread_id();
+    EXPECT_NE(previous_id, current_id);
+    previous_id = current_id;
+    a.Stop();
+  }
+}
+
 // Make sure Init() is called after Start() and before
 // WaitUntilThreadInitialized() returns.
 TEST_F(ThreadTest, SleepInsideInit) {
   SleepInsideInitThread t;
   EXPECT_FALSE(t.InitCalled());
   t.StartAndWaitForTesting();
   EXPECT_TRUE(t.InitCalled());
 }
 
 // Make sure that the destruction sequence is:
@@ skipping 25 matching lines @@
   ASSERT_EQ(static_cast<size_t>(THREAD_NUM_EVENTS), captured_events.size());
   EXPECT_EQ(THREAD_EVENT_INIT, captured_events[0]);
   EXPECT_EQ(THREAD_EVENT_CLEANUP, captured_events[1]);
   EXPECT_EQ(THREAD_EVENT_MESSAGE_LOOP_DESTROYED, captured_events[2]);
 }
 
 TEST_F(ThreadTest, ThreadNotStarted) {
   Thread a("Inert");
   EXPECT_EQ(nullptr, a.task_runner());
 }