Revert 111695 - Have content/ create and destroy its own threads.

chrome/browser/io_thread.cc

Index: chrome/browser/io_thread.cc
===================================================================
--- chrome/browser/io_thread.cc	(revision 111697)
+++ chrome/browser/io_thread.cc	(working copy)
@@ -316,8 +316,7 @@
 SystemURLRequestContextGetter::SystemURLRequestContextGetter(
     IOThread* io_thread)
     : io_thread_(io_thread),
-      io_message_loop_proxy_(
-          BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO)) {
+      io_message_loop_proxy_(io_thread->message_loop_proxy()) {
 }
 
 SystemURLRequestContextGetter::~SystemURLRequestContextGetter() {}
@@ -348,7 +347,8 @@
     PrefService* local_state,
     ChromeNetLog* net_log,
     ExtensionEventRouterForwarder* extension_event_router_forwarder)
-    : net_log_(net_log),
+    : content::BrowserProcessSubThread(BrowserThread::IO),
+      net_log_(net_log),
       extension_event_router_forwarder_(extension_event_router_forwarder),
       globals_(NULL),
       sdch_manager_(NULL),
@@ -371,17 +371,17 @@
                                                     local_state);
   ssl_config_service_manager_.reset(
       SSLConfigServiceManager::CreateDefaultManager(local_state));
-
-  BrowserThread::SetDelegate(BrowserThread::IO, this);
+  MessageLoop::current()->PostTask(
+      FROM_HERE, base::Bind(&IOThread::InitSystemRequestContext,
+                            weak_factory_.GetWeakPtr()));
 }
 
 IOThread::~IOThread() {
-  // This isn't needed for production code, but in tests, IOThread may
-  // be multiply constructed.
-  BrowserThread::SetDelegate(BrowserThread::IO, NULL);
-
   if (pref_proxy_config_tracker_.get())
     pref_proxy_config_tracker_->DetachFromPrefService();
+  // We cannot rely on our base class to stop the thread since we want our
+  // CleanUp function to run.
+  Stop();
   DCHECK(!globals_);
 }
 
@@ -407,8 +407,10 @@
   // messages around; it shouldn't be allowed to perform any blocking disk I/O.
   base::ThreadRestrictions::SetIOAllowed(false);
 
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  content::BrowserProcessSubThread::Init();
 
+  DCHECK_EQ(MessageLoop::TYPE_IO, message_loop()->type());
+
 #if defined(USE_NSS)
   net::SetMessageLoopForOCSP();
 #endif  // defined(USE_NSS)
@@ -478,26 +480,6 @@
 
   sdch_manager_ = new net::SdchManager();
   sdch_manager_->set_sdch_fetcher(new SdchDictionaryFetcher);
-
-  // InitSystemRequestContext turns right around and posts a task back
-  // to the IO thread, so we can't let it run until we know the IO
-  // thread has started.
-  //
-  // Note that since we are at BrowserThread::Init time, the UI thread
-  // is blocked waiting for the thread to start.  Therefore, posting
-  // this task to the main thread's message loop here is guaranteed to
-  // get it onto the message loop while the IOThread object still
-  // exists.  However, the message might not be processed on the UI
-  // thread until after IOThread is gone, so use a weak pointer.
-  BrowserThread::PostTask(BrowserThread::UI,
-                          FROM_HERE,
-                          base::Bind(&IOThread::InitSystemRequestContext,
-                                     weak_factory_.GetWeakPtr()));
-
-  // We constructed the weak pointer on the IO thread but it will be
-  // used on the UI thread.  Call this to avoid a thread checker
-  // error.
-  weak_factory_.DetachFromThread();
 }
 
 void IOThread::CleanUp() {
@@ -538,6 +520,10 @@
   base::debug::LeakTracker<net::URLRequest>::CheckForLeaks();
 
   base::debug::LeakTracker<SystemURLRequestContextGetter>::CheckForLeaks();
+
+  // This will delete the |notification_service_|.  Make sure it's done after
+  // anything else can reference it.
+  content::BrowserProcessSubThread::CleanUp();
 }
 
 // static
@@ -588,11 +574,6 @@
     host_cache->clear();
 }
 
-MessageLoop* IOThread::message_loop() const {
-  return BrowserThread::UnsafeGetBrowserThread(
-      BrowserThread::IO)->message_loop();
-}
-
 net::SSLConfigService* IOThread::GetSSLConfigService() {
   return ssl_config_service_manager_->Get();
 }
@@ -612,8 +593,6 @@
   }
   system_url_request_context_getter_ =
       new SystemURLRequestContextGetter(this);
-  // Safe to post an unretained this pointer, since IOThread is
-  // guaranteed to outlive the IO BrowserThread.
   message_loop()->PostTask(
       FROM_HERE, base::Bind(&IOThread::InitSystemRequestContextOnIOThread,
                             base::Unretained(this)));