Revert 66719 - Reland r65996. Disallows Singletons on non-joinable thread....

base/tracked_objects.cc

Index: base/tracked_objects.cc
===================================================================
--- base/tracked_objects.cc	(revision 66790)
+++ base/tracked_objects.cc	(working copy)
@@ -10,7 +10,6 @@
 #include "base/message_loop.h"
 #include "base/string_util.h"
 #include "base/stringprintf.h"
-#include "base/thread_restrictions.h"
 
 using base::TimeDelta;
 
@@ -90,13 +89,7 @@
 // static
 ThreadData::Status ThreadData::status_ = ThreadData::UNINITIALIZED;
 
-ThreadData::ThreadData() : next_(NULL) {
-  // This shouldn't use the MessageLoop::current() LazyInstance since this might
-  // be used on a non-joinable thread.
-  // http://crbug.com/62728
-  base::ThreadRestrictions::ScopedAllowSingleton scoped_allow_singleton;
-  message_loop_ = MessageLoop::current();
-}
+ThreadData::ThreadData() : next_(NULL), message_loop_(MessageLoop::current()) {}
 
 ThreadData::~ThreadData() {}
 
@@ -267,14 +260,8 @@
 }
 
 Births* ThreadData::TallyABirth(const Location& location) {
-  {
-    // This shouldn't use the MessageLoop::current() LazyInstance since this
-    // might be used on a non-joinable thread.
-    // http://crbug.com/62728
-    base::ThreadRestrictions::ScopedAllowSingleton scoped_allow_singleton;
-    if (!message_loop_)  // In case message loop wasn't yet around...
-      message_loop_ = MessageLoop::current();  // Find it now.
-  }
+  if (!message_loop_)  // In case message loop wasn't yet around...
+    message_loop_ = MessageLoop::current();  // Find it now.
 
   BirthMap::iterator it = birth_map_.find(location);
   if (it != birth_map_.end()) {
@@ -292,12 +279,8 @@
 
 void ThreadData::TallyADeath(const Births& lifetimes,
                              const TimeDelta& duration) {
-  {
-    // http://crbug.com/62728
-    base::ThreadRestrictions::ScopedAllowSingleton scoped_allow_singleton;
-    if (!message_loop_)  // In case message loop wasn't yet around...
-      message_loop_ = MessageLoop::current();  // Find it now.
-  }
+  if (!message_loop_)  // In case message loop wasn't yet around...
+    message_loop_ = MessageLoop::current();  // Find it now.
 
   DeathMap::iterator it = death_map_.find(&lifetimes);
   if (it != death_map_.end()) {