Revert 116816 - Hook up the SequencedWorkerPool to the browser thread.

This does some refactoring of the static data in the browser thread so we only have one global object instead of a bunch fo separate arrays.

It also hooks up the visited link master's I/O to use this new system as a proof of concept.
Review URL: http://codereview.chromium.org/9065009

TBR=brettw@chromium.org
Review URL: http://codereview.chromium.org/9122022

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@116817 0039d316-1c4b-4281-b951-d872f2087c98

9 files changed, 76 insertions, 211 deletions

diff --git a/base/threading/sequenced_worker_pool.cc b/base/threading/sequenced_worker_pool.cc
index 0a3697b..05ccff1 100644
--- a/base/threading/sequenced_worker_pool.cc
+++ b/base/threading/sequenced_worker_pool.cc
@@ -57,31 +57,20 @@ class SequencedWorkerPool::Inner
   Inner(size_t max_threads, const std::string& thread_name_prefix);
   virtual ~Inner();
 
+  // Backends for SequenceWorkerPool.
   SequenceToken GetSequenceToken();
-
   SequenceToken GetNamedSequenceToken(const std::string& name);
-
-  // This function accepts a name and an ID. If the name is null, the
-  // token ID is used. This allows us to implement the optional name lookup
-  // from a single function without having to enter the lock a separate time.
-  bool PostTask(const std::string* optional_token_name,
-                int sequence_token_id,
+  bool PostTask(int sequence_token_id,
                 SequencedWorkerPool::WorkerShutdown shutdown_behavior,
                 const tracked_objects::Location& from_here,
                 const base::Closure& task);
-
   void Shutdown();
-
   void SetTestingObserver(SequencedWorkerPool::TestingObserver* observer);
 
   // Runs the worker loop on the background thread.
   void ThreadLoop(Worker* this_worker);
 
  private:
-  // Called from within the lock, this converts the given token name into a
-  // token ID, creating a new one if necessary.
-  int LockedGetNamedTokenID(const std::string& name);
-
   // The calling code should clear the given delete_these_oustide_lock
   // vector the next time the lock is released. See the implementation for
   // a more detailed description.
@@ -246,11 +235,18 @@ SequencedWorkerPool::SequenceToken
 SequencedWorkerPool::Inner::GetNamedSequenceToken(
     const std::string& name) {
   base::AutoLock lock(lock_);
-  return SequenceToken(LockedGetNamedTokenID(name));
+  std::map<std::string, int>::const_iterator found =
+      named_sequence_tokens_.find(name);
+  if (found != named_sequence_tokens_.end())
+    return SequenceToken(found->second);  // Got an existing one.
+
+  // Create a new one for this name.
+  SequenceToken result = GetSequenceToken();
+  named_sequence_tokens_.insert(std::make_pair(name, result.id_));
+  return result;
 }
 
 bool SequencedWorkerPool::Inner::PostTask(
-    const std::string* optional_token_name,
     int sequence_token_id,
     SequencedWorkerPool::WorkerShutdown shutdown_behavior,
     const tracked_objects::Location& from_here,
@@ -267,10 +263,6 @@ bool SequencedWorkerPool::Inner::PostTask(
     if (terminating_)
       return false;
 
-    // Now that we have the lock, apply the named token rules.
-    if (optional_token_name)
-      sequenced.sequence_token_id = LockedGetNamedTokenID(*optional_token_name);
-
     pending_tasks_.push_back(sequenced);
     pending_task_count_++;
     if (shutdown_behavior == BLOCK_SHUTDOWN)
@@ -385,22 +377,6 @@ void SequencedWorkerPool::Inner::ThreadLoop(Worker* this_worker) {
   cond_var_.Signal();
 }
 
-int SequencedWorkerPool::Inner::LockedGetNamedTokenID(
-    const std::string& name) {
-  lock_.AssertAcquired();
-  DCHECK(!name.empty());
-
-  std::map<std::string, int>::const_iterator found =
-      named_sequence_tokens_.find(name);
-  if (found != named_sequence_tokens_.end())
-    return found->second;  // Got an existing one.
-
-  // Create a new one for this name.
-  SequenceToken result = GetSequenceToken();
-  named_sequence_tokens_.insert(std::make_pair(name, result.id_));
-  return result.id_;
-}
-
 bool SequencedWorkerPool::Inner::GetWork(
     SequencedTask* task,
     std::vector<base::Closure>* delete_these_outside_lock) {
@@ -617,38 +593,30 @@ SequencedWorkerPool::SequenceToken SequencedWorkerPool::GetNamedSequenceToken(
 bool SequencedWorkerPool::PostWorkerTask(
     const tracked_objects::Location& from_here,
     const base::Closure& task) {
-  return inner_->PostTask(NULL, 0, BLOCK_SHUTDOWN, from_here, task);
+  return inner_->PostTask(0, BLOCK_SHUTDOWN, from_here, task);
 }
 
 bool SequencedWorkerPool::PostWorkerTaskWithShutdownBehavior(
     const tracked_objects::Location& from_here,
     const base::Closure& task,
     WorkerShutdown shutdown_behavior) {
-  return inner_->PostTask(NULL, 0, shutdown_behavior, from_here, task);
+  return inner_->PostTask(0, shutdown_behavior, from_here, task);
 }
 
 bool SequencedWorkerPool::PostSequencedWorkerTask(
     SequenceToken sequence_token,
     const tracked_objects::Location& from_here,
     const base::Closure& task) {
-  return inner_->PostTask(NULL, sequence_token.id_, BLOCK_SHUTDOWN,
+  return inner_->PostTask(sequence_token.id_, BLOCK_SHUTDOWN,
                           from_here, task);
 }
 
-bool SequencedWorkerPool::PostNamedSequencedWorkerTask(
-    const std::string& token_name,
-    const tracked_objects::Location& from_here,
-    const base::Closure& task) {
-  DCHECK(!token_name.empty());
-  return inner_->PostTask(&token_name, 0, BLOCK_SHUTDOWN, from_here, task);
-}
-
 bool SequencedWorkerPool::PostSequencedWorkerTaskWithShutdownBehavior(
     SequenceToken sequence_token,
     const tracked_objects::Location& from_here,
     const base::Closure& task,
     WorkerShutdown shutdown_behavior) {
-  return inner_->PostTask(NULL, sequence_token.id_, shutdown_behavior,
+  return inner_->PostTask(sequence_token.id_, shutdown_behavior,
                           from_here, task);
 }
 
diff --git a/base/threading/sequenced_worker_pool.h b/base/threading/sequenced_worker_pool.h
index 71e431c..c6e0560 100644
--- a/base/threading/sequenced_worker_pool.h
+++ b/base/threading/sequenced_worker_pool.h
@@ -172,12 +172,6 @@ class BASE_EXPORT SequencedWorkerPool {
                                const tracked_objects::Location& from_here,
                                const base::Closure& task);
 
-  // Like PostSequencedWorkerTask above, but allows you to specify a named
-  // token, which saves an extra call to GetNamedSequenceToken.
-  bool PostNamedSequencedWorkerTask(const std::string& token_name,
-                                    const tracked_objects::Location& from_here,
-                                    const base::Closure& task);
-
   // Same as PostSequencedWorkerTask but allows specification of the shutdown
   // behavior.
   bool PostSequencedWorkerTaskWithShutdownBehavior(
diff --git a/chrome/browser/crash_upload_list.cc b/chrome/browser/crash_upload_list.cc
index 30c04f8..bc74d8e 100644
--- a/chrome/browser/crash_upload_list.cc
+++ b/chrome/browser/crash_upload_list.cc
@@ -39,7 +39,8 @@ CrashUploadList::CrashUploadList(Delegate* delegate) : delegate_(delegate) {}
 CrashUploadList::~CrashUploadList() {}
 
 void CrashUploadList::LoadCrashListAsynchronously() {
-  BrowserThread::PostBlockingPoolTask(
+  BrowserThread::PostTask(
+      BrowserThread::FILE,
       FROM_HERE,
       base::Bind(&CrashUploadList::LoadCrashListAndInformDelegateOfCompletion,
                  this));
@@ -59,6 +60,7 @@ void CrashUploadList::LoadCrashListAndInformDelegateOfCompletion() {
 }
 
 void CrashUploadList::LoadCrashList() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
   FilePath crash_dir_path;
   PathService::Get(chrome::DIR_CRASH_DUMPS, &crash_dir_path);
   FilePath upload_log_path = crash_dir_path.AppendASCII("uploads.log");
diff --git a/chrome/browser/visitedlink/visitedlink_master.cc b/chrome/browser/visitedlink/visitedlink_master.cc
index 38c87ca..f3fbc85 100644
--- a/chrome/browser/visitedlink/visitedlink_master.cc
+++ b/chrome/browser/visitedlink/visitedlink_master.cc
@@ -191,7 +191,6 @@ void VisitedLinkMaster::InitMembers(Listener* listener, Profile* profile) {
   history_service_override_ = NULL;
   suppress_rebuild_ = false;
   profile_ = profile;
-  sequence_token_ = BrowserThread::GetBlockingPool()->GetSequenceToken();
 
 #ifndef NDEBUG
   posted_asynchronous_operation_ = false;
@@ -243,12 +242,6 @@ VisitedLinkMaster::Hash VisitedLinkMaster::TryToAddURL(const GURL& url) {
   return AddFingerprint(fingerprint, true);
 }
 
-void VisitedLinkMaster::PostIOTask(const tracked_objects::Location& from_here,
-                                   const base::Closure& task) {
-  BrowserThread::GetBlockingPool()->PostSequencedWorkerTask(sequence_token_,
-                                                            from_here, task);
-}
-
 void VisitedLinkMaster::AddURL(const GURL& url) {
   Hash index = TryToAddURL(url);
   if (!table_builder_ && index != null_hash_) {
@@ -487,7 +480,10 @@ bool VisitedLinkMaster::WriteFullTable() {
               hash_table_, table_length_ * sizeof(Fingerprint));
 
   // The hash table may have shrunk, so make sure this is the end.
-  PostIOTask(FROM_HERE, base::Bind(base::IgnoreResult(&TruncateFile), file_));
+  BrowserThread::PostTask(
+      BrowserThread::FILE,
+      FROM_HERE,
+      base::Bind(base::IgnoreResult(&TruncateFile), file_));
   return true;
 }
 
@@ -677,7 +673,11 @@ void VisitedLinkMaster::FreeURLTable() {
   }
   if (!file_)
     return;
-  PostIOTask(FROM_HERE, base::Bind(base::IgnoreResult(&fclose), file_));
+
+  BrowserThread::PostTask(
+      BrowserThread::FILE,
+      FROM_HERE,
+      base::Bind(base::IgnoreResult(&fclose), file_));
 }
 
 bool VisitedLinkMaster::ResizeTableIfNecessary() {
@@ -860,7 +860,9 @@ void VisitedLinkMaster::WriteToFile(FILE* file,
 #ifndef NDEBUG
   posted_asynchronous_operation_ = true;
 #endif
-  PostIOTask(FROM_HERE,
+
+  BrowserThread::PostTask(
+      BrowserThread::FILE, FROM_HERE,
       base::Bind(&AsyncWrite, file, offset,
                  std::string(static_cast<const char*>(data), data_size)));
 }
diff --git a/chrome/browser/visitedlink/visitedlink_master.h b/chrome/browser/visitedlink/visitedlink_master.h
index 1771afe..c84e809 100644
--- a/chrome/browser/visitedlink/visitedlink_master.h
+++ b/chrome/browser/visitedlink/visitedlink_master.h
@@ -17,7 +17,6 @@
 #include "base/gtest_prod_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/shared_memory.h"
-#include "base/threading/sequenced_worker_pool.h"
 #include "chrome/browser/history/history.h"
 #include "chrome/common/visitedlink_common.h"
 
@@ -164,10 +163,6 @@ class VisitedLinkMaster : public VisitedLinkCommon {
   // File I/O functions
   // ------------------
 
-  // Posts the given task to the blocking worker pool with our options.
-  void PostIOTask(const tracked_objects::Location& from_here,
-                  const base::Closure& task);
-
   // Writes the entire table to disk, returning true on success. It will leave
   // the table file open and the handle to it in file_
   bool WriteFullTable();
@@ -317,9 +312,6 @@ class VisitedLinkMaster : public VisitedLinkCommon {
   // (it knows the path to where the data is stored)
   Profile* profile_;
 
-  // Lazily initialized sequence token for posting file tasks.
-  base::SequencedWorkerPool::SequenceToken sequence_token_;
-
   // When non-NULL, indicates we are in database rebuild mode and points to
   // the class collecting fingerprint information from the history system.
   // The pointer is owned by this class, but it must remain valid while the
diff --git a/content/browser/browser_main_loop.cc b/content/browser/browser_main_loop.cc
index e22fd15..2a1f681 100644
--- a/content/browser/browser_main_loop.cc
+++ b/content/browser/browser_main_loop.cc
@@ -497,14 +497,6 @@ void BrowserMainLoop::ShutdownThreadsAndCleanUp() {
       parts_->PostStopThread(id);
   }
 
-  // Close the blocking I/O pool after the other threads. Other threads such
-  // as the I/O thread may need to schedule work like closing files or flushing
-  // data during shutdown, so the blocking pool needs to be available. There
-  // may also be slow operations pending that will blcok shutdown, so closing
-  // it here (which will block until required operations are complete) gives
-  // more head start for those operations to finish.
-  BrowserThreadImpl::ShutdownThreadPool();
-
   if (parts_.get())
     parts_->PostDestroyThreads();
 }
diff --git a/content/browser/browser_thread_impl.cc b/content/browser/browser_thread_impl.cc
index fd86aa5..a66477a 100644
--- a/content/browser/browser_thread_impl.cc
+++ b/content/browser/browser_thread_impl.cc
@@ -9,7 +9,6 @@
 #include "base/lazy_instance.h"
 #include "base/message_loop.h"
 #include "base/message_loop_proxy.h"
-#include "base/threading/sequenced_worker_pool.h"
 #include "base/threading/thread_restrictions.h"
 
 namespace content {
@@ -31,37 +30,24 @@ static const char* g_browser_thread_names[BrowserThread::ID_COUNT] = {
 #endif
 };
 
-struct BrowserThreadGlobals {
-  BrowserThreadGlobals()
-      : blocking_pool(new base::SequencedWorkerPool(3, "BrowserBlocking")) {
-    memset(threads, 0,
-           BrowserThread::ID_COUNT * sizeof(BrowserThreadImpl*));
-    memset(thread_delegates, 0,
-           BrowserThread::ID_COUNT * sizeof(BrowserThreadDelegate*));
-  }
-
-  // This lock protects |threads|. Do not read or modify that array
-  // without holding this lock. Do not block while holding this lock.
-  base::Lock lock;
-
-  // This array is protected by |lock|. The threads are not owned by this
-  // array. Typically, the threads are owned on the UI thread by
-  // content::BrowserMainLoop. BrowserThreadImpl objects remove themselves from
-  // this array upon destruction.
-  BrowserThreadImpl* threads[BrowserThread::ID_COUNT];
-
-  // Only atomic operations are used on this array. The delegates are not owned
-  // by this array, rather by whoever calls BrowserThread::SetDelegate.
-  BrowserThreadDelegate* thread_delegates[BrowserThread::ID_COUNT];
-
-  // This pointer is deliberately leaked on shutdown. This allows the pool to
-  // implement "continue on shutdown" semantics.
-  base::SequencedWorkerPool* blocking_pool;
-};
-
-base::LazyInstance<BrowserThreadGlobals,
-                   base::LeakyLazyInstanceTraits<BrowserThreadGlobals> >
-    g_globals = LAZY_INSTANCE_INITIALIZER;
+// This lock protects |g_browser_threads|.  Do not read or modify that
+// array without holding this lock.  Do not block while holding this
+// lock.
+base::LazyInstance<base::Lock,
+                   base::LeakyLazyInstanceTraits<base::Lock> >
+    g_lock = LAZY_INSTANCE_INITIALIZER;
+
+// This array is protected by |g_lock|.  The threads are not owned by this
+// array. Typically, the threads are owned on the UI thread by
+// content::BrowserMainLoop.  BrowserThreadImpl objects remove
+// themselves from this array upon destruction.
+static BrowserThreadImpl* g_browser_threads[BrowserThread::ID_COUNT];
+
+// Only atomic operations are used on this array.  The delegates are
+// not owned by this array, rather by whoever calls
+// BrowserThread::SetDelegate.
+static BrowserThreadDelegate* g_browser_thread_delegates[
+    BrowserThread::ID_COUNT];
 
 }  // namespace
 
@@ -79,18 +65,10 @@ BrowserThreadImpl::BrowserThreadImpl(ID identifier,
   Initialize();
 }
 
-// static
-void BrowserThreadImpl::ShutdownThreadPool() {
-  BrowserThreadGlobals& globals = g_globals.Get();
-  globals.blocking_pool->Shutdown();
-}
-
 void BrowserThreadImpl::Init() {
-  BrowserThreadGlobals& globals = g_globals.Get();
-
   using base::subtle::AtomicWord;
   AtomicWord* storage =
-      reinterpret_cast<AtomicWord*>(&globals.thread_delegates[identifier_]);
+      reinterpret_cast<AtomicWord*>(&g_browser_thread_delegates[identifier_]);
   AtomicWord stored_pointer = base::subtle::NoBarrier_Load(storage);
   BrowserThreadDelegate* delegate =
       reinterpret_cast<BrowserThreadDelegate*>(stored_pointer);
@@ -99,11 +77,9 @@ void BrowserThreadImpl::Init() {
 }
 
 void BrowserThreadImpl::CleanUp() {
-  BrowserThreadGlobals& globals = g_globals.Get();
-
   using base::subtle::AtomicWord;
   AtomicWord* storage =
-      reinterpret_cast<AtomicWord*>(&globals.thread_delegates[identifier_]);
+      reinterpret_cast<AtomicWord*>(&g_browser_thread_delegates[identifier_]);
   AtomicWord stored_pointer = base::subtle::NoBarrier_Load(storage);
   BrowserThreadDelegate* delegate =
       reinterpret_cast<BrowserThreadDelegate*>(stored_pointer);
@@ -113,12 +89,10 @@ void BrowserThreadImpl::CleanUp() {
 }
 
 void BrowserThreadImpl::Initialize() {
-  BrowserThreadGlobals& globals = g_globals.Get();
-
-  base::AutoLock lock(globals.lock);
+  base::AutoLock lock(g_lock.Get());
   DCHECK(identifier_ >= 0 && identifier_ < ID_COUNT);
-  DCHECK(globals.threads[identifier_] == NULL);
-  globals.threads[identifier_] = this;
+  DCHECK(g_browser_threads[identifier_] == NULL);
+  g_browser_threads[identifier_] = this;
 }
 
 BrowserThreadImpl::~BrowserThreadImpl() {
@@ -127,13 +101,12 @@ BrowserThreadImpl::~BrowserThreadImpl() {
   // the right BrowserThread.
   Stop();
 
-  BrowserThreadGlobals& globals = g_globals.Get();
-  base::AutoLock lock(globals.lock);
-  globals.threads[identifier_] = NULL;
+  base::AutoLock lock(g_lock.Get());
+  g_browser_threads[identifier_] = NULL;
 #ifndef NDEBUG
   // Double check that the threads are ordered correctly in the enumeration.
   for (int i = identifier_ + 1; i < ID_COUNT; ++i) {
-    DCHECK(!globals.threads[i]) <<
+    DCHECK(!g_browser_threads[i]) <<
         "Threads must be listed in the reverse order that they die";
   }
 #endif
@@ -158,12 +131,11 @@ bool BrowserThreadImpl::PostTaskHelper(
       GetCurrentThreadIdentifier(&current_thread) &&
       current_thread <= identifier;
 
-  BrowserThreadGlobals& globals = g_globals.Get();
   if (!guaranteed_to_outlive_target_thread)
-    globals.lock.Acquire();
+    g_lock.Get().Acquire();
 
-  MessageLoop* message_loop = globals.threads[identifier] ?
-      globals.threads[identifier]->message_loop() : NULL;
+  MessageLoop* message_loop = g_browser_threads[identifier] ?
+      g_browser_threads[identifier]->message_loop() : NULL;
   if (message_loop) {
     if (nestable) {
       message_loop->PostDelayedTask(from_here, task, delay_ms);
@@ -173,7 +145,7 @@ bool BrowserThreadImpl::PostTaskHelper(
   }
 
   if (!guaranteed_to_outlive_target_thread)
-    globals.lock.Release();
+    g_lock.Get().Release();
 
   return !!message_loop;
 }
@@ -220,32 +192,10 @@ class BrowserThreadMessageLoopProxy : public base::MessageLoopProxy {
 };
 
 // static
-bool BrowserThread::PostBlockingPoolTask(
-    const tracked_objects::Location& from_here,
-    const base::Closure& task) {
-  return g_globals.Get().blocking_pool->PostWorkerTask(from_here, task);
-}
-
-// static
-bool BrowserThread::PostBlockingPoolSequencedTask(
-    const std::string& sequence_token_name,
-    const tracked_objects::Location& from_here,
-    const base::Closure& task) {
-  return g_globals.Get().blocking_pool->PostNamedSequencedWorkerTask(
-      sequence_token_name, from_here, task);
-}
-
-// static
-base::SequencedWorkerPool* BrowserThread::GetBlockingPool() {
-  return g_globals.Get().blocking_pool;
-}
-
-// static
 bool BrowserThread::IsWellKnownThread(ID identifier) {
-  BrowserThreadGlobals& globals = g_globals.Get();
-  base::AutoLock lock(globals.lock);
+  base::AutoLock lock(g_lock.Get());
   return (identifier >= 0 && identifier < ID_COUNT &&
-          globals.threads[identifier]);
+          g_browser_threads[identifier]);
 }
 
 // static
@@ -255,21 +205,19 @@ bool BrowserThread::CurrentlyOn(ID identifier) {
   // function.
   // http://crbug.com/63678
   base::ThreadRestrictions::ScopedAllowSingleton allow_singleton;
-  BrowserThreadGlobals& globals = g_globals.Get();
-  base::AutoLock lock(globals.lock);
+  base::AutoLock lock(g_lock.Get());
   DCHECK(identifier >= 0 && identifier < ID_COUNT);
-  return globals.threads[identifier] &&
-         globals.threads[identifier]->message_loop() ==
+  return g_browser_threads[identifier] &&
+         g_browser_threads[identifier]->message_loop() ==
              MessageLoop::current();
 }
 
 // static
 bool BrowserThread::IsMessageLoopValid(ID identifier) {
-  BrowserThreadGlobals& globals = g_globals.Get();
-  base::AutoLock lock(globals.lock);
+  base::AutoLock lock(g_lock.Get());
   DCHECK(identifier >= 0 && identifier < ID_COUNT);
-  return globals.threads[identifier] &&
-         globals.threads[identifier]->message_loop();
+  return g_browser_threads[identifier] &&
+         g_browser_threads[identifier]->message_loop();
 }
 
 // static
@@ -327,11 +275,10 @@ bool BrowserThread::GetCurrentThreadIdentifier(ID* identifier) {
   // http://crbug.com/63678
   base::ThreadRestrictions::ScopedAllowSingleton allow_singleton;
   MessageLoop* cur_message_loop = MessageLoop::current();
-  BrowserThreadGlobals& globals = g_globals.Get();
   for (int i = 0; i < ID_COUNT; ++i) {
-    if (globals.threads[i] &&
-        globals.threads[i]->message_loop() == cur_message_loop) {
-      *identifier = globals.threads[i]->identifier_;
+    if (g_browser_threads[i] &&
+        g_browser_threads[i]->message_loop() == cur_message_loop) {
+      *identifier = g_browser_threads[i]->identifier_;
       return true;
     }
   }
@@ -341,7 +288,8 @@ bool BrowserThread::GetCurrentThreadIdentifier(ID* identifier) {
 
 // static
 scoped_refptr<base::MessageLoopProxy>
-BrowserThread::GetMessageLoopProxyForThread(ID identifier) {
+BrowserThread::GetMessageLoopProxyForThread(
+    ID identifier) {
   scoped_refptr<base::MessageLoopProxy> proxy(
       new BrowserThreadMessageLoopProxy(identifier));
   return proxy;
@@ -349,9 +297,8 @@ BrowserThread::GetMessageLoopProxyForThread(ID identifier) {
 
 // static
 MessageLoop* BrowserThread::UnsafeGetMessageLoopForThread(ID identifier) {
-  BrowserThreadGlobals& globals = g_globals.Get();
-  base::AutoLock lock(globals.lock);
-  base::Thread* thread = globals.threads[identifier];
+  base::AutoLock lock(g_lock.Get());
+  base::Thread* thread = g_browser_threads[identifier];
   DCHECK(thread);
   MessageLoop* loop = thread->message_loop();
   return loop;
@@ -361,9 +308,8 @@ MessageLoop* BrowserThread::UnsafeGetMessageLoopForThread(ID identifier) {
 void BrowserThread::SetDelegate(ID identifier,
                                 BrowserThreadDelegate* delegate) {
   using base::subtle::AtomicWord;
-  BrowserThreadGlobals& globals = g_globals.Get();
   AtomicWord* storage = reinterpret_cast<AtomicWord*>(
-      &globals.thread_delegates[identifier]);
+      &g_browser_thread_delegates[identifier]);
   AtomicWord old_pointer = base::subtle::NoBarrier_AtomicExchange(
       storage, reinterpret_cast<AtomicWord>(delegate));
 
diff --git a/content/browser/browser_thread_impl.h b/content/browser/browser_thread_impl.h
index 4488f85..feea986 100644
--- a/content/browser/browser_thread_impl.h
+++ b/content/browser/browser_thread_impl.h
@@ -25,8 +25,6 @@ class CONTENT_EXPORT BrowserThreadImpl
   BrowserThreadImpl(BrowserThread::ID identifier, MessageLoop* message_loop);
   virtual ~BrowserThreadImpl();
 
-  static void ShutdownThreadPool();
-
  protected:
   virtual void Init() OVERRIDE;
   virtual void CleanUp() OVERRIDE;
diff --git a/content/public/browser/browser_thread.h b/content/public/browser/browser_thread.h
index 02671c9..53345fa 100644
--- a/content/public/browser/browser_thread.h
+++ b/content/public/browser/browser_thread.h
@@ -20,7 +20,6 @@
 class MessageLoop;
 
 namespace base {
-class SequencedWorkerPool;
 class Thread;
 }
 
@@ -140,34 +139,6 @@ class CONTENT_EXPORT BrowserThread {
         from_here, object);
   }
 
-  // Simplified wrappers for posting to the blocking thread pool. Use this
-  // for doing things like blocking I/O.
-  //
-  // The first variant will run the task in the pool with no sequencing
-  // semantics, so may get run in parallel with other posted tasks. The
-  // second variant provides sequencing between tasks with the same
-  // sequence token name.
-  //
-  // These tasks are guaranteed to run before shutdown.
-  //
-  // If you need to provide different shutdown semantics (like you have
-  // something slow and noncritical that doesn't need to block shutdown),
-  // or you want to manually provide a sequence token (which saves a map
-  // lookup and is guaranteed unique without you having to come up with a
-  // unique string), you can access the sequenced worker pool directly via
-  // GetBlockingPool().
-  static bool PostBlockingPoolTask(const tracked_objects::Location& from_here,
-                                   const base::Closure& task);
-  static bool PostBlockingPoolSequencedTask(
-      const std::string& sequence_token_name,
-      const tracked_objects::Location& from_here,
-      const base::Closure& task);
-
-  // Returns the thread pool used for blocking file I/O. Use this object to
-  // perform random blocking operations such as file writes or querying the
-  // Windows registry.
-  static base::SequencedWorkerPool* GetBlockingPool();
-
   // Callable on any thread.  Returns whether the given ID corresponds to a well
   // known thread.
   static bool IsWellKnownThread(ID identifier);