Revert of Prevent data race in MessageQueue.

webrtc/base/messagequeue.cc

Index: webrtc/base/messagequeue.cc
diff --git a/webrtc/base/messagequeue.cc b/webrtc/base/messagequeue.cc
index 61aa61192bbad69d87ddf5e79aab3a5af3ce290f..bbdb941ffab4941107b347023f5ab23e0b762b42 100644
--- a/webrtc/base/messagequeue.cc
+++ b/webrtc/base/messagequeue.cc
@@ -117,8 +117,8 @@
 // MessageQueue
 
 MessageQueue::MessageQueue(SocketServer* ss, bool init_queue)
-    : fStop_(false), fPeekKeep_(false),
-      dmsgq_next_num_(0), fInitialized_(false), fDestroyed_(false), ss_(ss) {
+    : ss_(ss), fStop_(false), fPeekKeep_(false),
+      dmsgq_next_num_(0), fInitialized_(false), fDestroyed_(false) {
   if (!ss_) {
     // Currently, MessageQueue holds a socket server, and is the base class for
     // Thread.  It seems like it makes more sense for Thread to hold the socket
@@ -159,37 +159,19 @@
   SignalQueueDestroyed();
   MessageQueueManager::Remove(this);
   Clear(NULL);
-
-  SharedScope ss(&ss_lock_);
   if (ss_) {
     ss_->SetMessageQueue(NULL);
   }
 }
 
-SocketServer* MessageQueue::socketserver() {
-  SharedScope ss(&ss_lock_);
-  return ss_;
-}
-
 void MessageQueue::set_socketserver(SocketServer* ss) {
-  // Need to lock exclusively here to prevent simultaneous modifications from
-  // other threads. Can't be a shared lock to prevent races with other reading
-  // threads.
-  // Other places that only read "ss_" can use a shared lock as simultaneous
-  // read access is allowed.
-  ExclusiveScope es(&ss_lock_);
   ss_ = ss ? ss : default_ss_.get();
   ss_->SetMessageQueue(this);
 }
 
-void MessageQueue::WakeUpSocketServer() {
-  SharedScope ss(&ss_lock_);
-  ss_->WakeUp();
-}
-
 void MessageQueue::Quit() {
   fStop_ = true;
-  WakeUpSocketServer();
+  ss_->WakeUp();
 }
 
 bool MessageQueue::IsQuitting() {
@@ -295,12 +277,9 @@
         cmsNext = cmsDelayNext;
     }
 
-    {
-      // Wait and multiplex in the meantime
-      SharedScope ss(&ss_lock_);
-      if (!ss_->Wait(cmsNext, process_io))
-        return false;
-    }
+    // Wait and multiplex in the meantime
+    if (!ss_->Wait(cmsNext, process_io))
+      return false;
 
     // If the specified timeout expired, return
 
@@ -328,18 +307,16 @@
   // Add the message to the end of the queue
   // Signal for the multiplexer to return
 
-  {
-    CritScope cs(&crit_);
-    Message msg;
-    msg.phandler = phandler;
-    msg.message_id = id;
-    msg.pdata = pdata;
-    if (time_sensitive) {
-      msg.ts_sensitive = Time() + kMaxMsgLatency;
-    }
-    msgq_.push_back(msg);
-  }
-  WakeUpSocketServer();
+  CritScope cs(&crit_);
+  Message msg;
+  msg.phandler = phandler;
+  msg.message_id = id;
+  msg.pdata = pdata;
+  if (time_sensitive) {
+    msg.ts_sensitive = Time() + kMaxMsgLatency;
+  }
+  msgq_.push_back(msg);
+  ss_->WakeUp();
 }
 
 void MessageQueue::PostDelayed(int cmsDelay,
@@ -368,20 +345,18 @@
   // Add to the priority queue. Gets sorted soonest first.
   // Signal for the multiplexer to return.
 
-  {
-    CritScope cs(&crit_);
-    Message msg;
-    msg.phandler = phandler;
-    msg.message_id = id;
-    msg.pdata = pdata;
-    DelayedMessage dmsg(cmsDelay, tstamp, dmsgq_next_num_, msg);
-    dmsgq_.push(dmsg);
-    // If this message queue processes 1 message every millisecond for 50 days,
-    // we will wrap this number.  Even then, only messages with identical times
-    // will be misordered, and then only briefly.  This is probably ok.
-    VERIFY(0 != ++dmsgq_next_num_);
-  }
-  WakeUpSocketServer();
+  CritScope cs(&crit_);
+  Message msg;
+  msg.phandler = phandler;
+  msg.message_id = id;
+  msg.pdata = pdata;
+  DelayedMessage dmsg(cmsDelay, tstamp, dmsgq_next_num_, msg);
+  dmsgq_.push(dmsg);
+  // If this message queue processes 1 message every millisecond for 50 days,
+  // we will wrap this number.  Even then, only messages with identical times
+  // will be misordered, and then only briefly.  This is probably ok.
+  VERIFY(0 != ++dmsgq_next_num_);
+  ss_->WakeUp();
 }
 
 int MessageQueue::GetDelay() {