Base: Don't overwrite the thread id when ThreadMain exits. There's

base/threading/thread.cc

Index: base/threading/thread.cc
===================================================================
--- base/threading/thread.cc	(revision 138018)
+++ base/threading/thread.cc	(working copy)
@@ -47,6 +47,7 @@
 Thread::Thread(const char* name)
     : started_(false),
       stopping_(false),
+      running_(false),
       startup_data_(NULL),
       thread_(0),
       message_loop_(NULL),
@@ -124,6 +125,10 @@
   message_loop_->PostTask(FROM_HERE, base::Bind(&ThreadQuitHelper));
 }
 
+bool Thread::IsRunning() const {
+  return running_;
+}
+
 void Thread::Run(MessageLoop* message_loop) {
   message_loop->Run();
 }
@@ -160,7 +165,9 @@
     // startup_data_ can't be touched anymore since the starting thread is now
     // unlocked.
 
+    running_ = true;
     Run(message_loop_);
+    running_ = false;
 
     // Let the thread do extra cleanup.
     CleanUp();
@@ -171,7 +178,6 @@
     // We can't receive messages anymore.
     message_loop_ = NULL;
   }
-  thread_id_ = kInvalidThreadId;
 }
 
 }  // namespace base