Revert 43127 [It resulted in a free memory write because of a consumer that was relying on the old ordering (BUG=39932).]

Don't call Thread::CleanUp() before the MessageLoop destruction observers have run.

This is consistent with the comment for Thread::CleanUp(), which says it runs after the message loop has "stopped".
Certain consumers depend on this ordering to avoid accessing variables which are deleted by Thread::CleanUp().

BUG=39723
TEST=ThreadTest.CleanUp

Review URL: http://codereview.chromium.org/1540002

TBR=eroman@chromium.org
Review URL: http://codereview.chromium.org/1517006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@43174 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 20 insertions, 24 deletions

diff --git a/base/thread.cc b/base/thread.cc
index e916f2c..aeaa0a1 100644
--- a/base/thread.cc
+++ b/base/thread.cc
@@ -35,7 +35,7 @@ struct Thread::StartupData {
         event(false, false) {}
 };
 
-Thread::Thread(const char* name)
+Thread::Thread(const char *name)
     : stopping_(false),
       startup_data_(NULL),
       thread_(0),
@@ -134,30 +134,25 @@ void Thread::Run(MessageLoop* message_loop) {
 }
 
 void Thread::ThreadMain() {
-  {
-    // The message loop for this thread.
-    MessageLoop message_loop(startup_data_->options.message_loop_type);
-
-    // Complete the initialization of our Thread object.
-    thread_id_ = PlatformThread::CurrentId();
-    PlatformThread::SetName(name_.c_str());
-    ANNOTATE_THREAD_NAME(name_.c_str());  // Tell the name to race detector.
-    message_loop.set_thread_name(name_);
-    message_loop_ = &message_loop;
-
-    // Let the thread do extra initialization.
-    // Let's do this before signaling we are started.
-    Init();
-
-    startup_data_->event.Signal();
-    // startup_data_ can't be touched anymore since the starting thread is now
-    // unlocked.
-
-    Run(message_loop_);
-    // Destroy |message_loop| upon leaving this scope.
-  }
+  // The message loop for this thread.
+  MessageLoop message_loop(startup_data_->options.message_loop_type);
 
-  message_loop_ = NULL;
+  // Complete the initialization of our Thread object.
+  thread_id_ = PlatformThread::CurrentId();
+  PlatformThread::SetName(name_.c_str());
+  ANNOTATE_THREAD_NAME(name_.c_str());  // Tell the name to race detector.
+  message_loop.set_thread_name(name_);
+  message_loop_ = &message_loop;
+
+  // Let the thread do extra initialization.
+  // Let's do this before signaling we are started.
+  Init();
+
+  startup_data_->event.Signal();
+  // startup_data_ can't be touched anymore since the starting thread is now
+  // unlocked.
+
+  Run(message_loop_);
 
   // Let the thread do extra cleanup.
   CleanUp();
@@ -166,6 +161,7 @@ void Thread::ThreadMain() {
   DCHECK(GetThreadWasQuitProperly());
 
   // We can't receive messages anymore.
+  message_loop_ = NULL;
   thread_id_ = 0;
 }