Fourth patch in getting rid of caching MessageLoop pointers.

BUG=25354
Review URL: http://codereview.chromium.org/348037

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@30751 0039d316-1c4b-4281-b951-d872f2087c98

5 files changed, 147 insertions, 225 deletions

diff --git a/chrome/browser/download/download_manager.cc b/chrome/browser/download/download_manager.cc
index 3ded94e..eef8b04 100644
--- a/chrome/browser/download/download_manager.cc
+++ b/chrome/browser/download/download_manager.cc
@@ -18,6 +18,7 @@
 #include "base/timer.h"
 #include "chrome/browser/browser_list.h"
 #include "chrome/browser/browser_process.h"
+#include "chrome/browser/chrome_thread.h"
 #include "chrome/browser/download/download_file.h"
 #include "chrome/browser/download/download_util.h"
 #include "chrome/browser/extensions/crx_installer.h"
@@ -347,9 +348,7 @@ void DownloadManager::RegisterUserPrefs(PrefService* prefs) {
 DownloadManager::DownloadManager()
     : shutdown_needed_(false),
       profile_(NULL),
-      file_manager_(NULL),
-      ui_loop_(MessageLoop::current()),
-      file_loop_(NULL) {
+      file_manager_(NULL) {
 }
 
 DownloadManager::~DownloadManager() {
@@ -494,12 +493,6 @@ bool DownloadManager::Init(Profile* profile) {
     return false;
   }
 
-  file_loop_ = g_browser_process->file_thread()->message_loop();
-  if (!file_loop_) {
-    NOTREACHED();
-    return false;
-  }
-
   // Get our user preference state.
   PrefService* prefs = profile_->GetPrefs();
   DCHECK(prefs);
@@ -513,8 +506,9 @@ bool DownloadManager::Init(Profile* profile) {
   // get rid of |CreateDirectoryPtr|.
   bool (*CreateDirectoryPtr)(const FilePath&) = &file_util::CreateDirectory;
   // Ensure that the download directory specified in the preferences exists.
-  file_loop_->PostTask(FROM_HERE, NewRunnableFunction(
-      CreateDirectoryPtr, download_path()));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableFunction(CreateDirectoryPtr, download_path()));
 
   // We use this to determine possibly dangerous downloads.
   download_util::InitializeExeTypes(&exe_types_);
@@ -551,7 +545,7 @@ void DownloadManager::QueryHistoryForDownloads() {
 // point. OnCreateDatabaseEntryComplete() handles that finalization of the the
 // download creation as a callback from the history thread.
 void DownloadManager::StartDownload(DownloadCreateInfo* info) {
-  DCHECK(MessageLoop::current() == ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
   DCHECK(info);
 
   // Freeze the user's preference for showing a Save As dialog.  We're going to
@@ -590,10 +584,10 @@ void DownloadManager::StartDownload(DownloadCreateInfo* info) {
 
   // We need to move over to the download thread because we don't want to stat
   // the suggested path on the UI thread.
-  file_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(this,
-                        &DownloadManager::CheckIfSuggestedPathExists,
-                        info));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(
+          this, &DownloadManager::CheckIfSuggestedPathExists, info));
 }
 
 void DownloadManager::CheckIfSuggestedPathExists(DownloadCreateInfo* info) {
@@ -647,14 +641,15 @@ void DownloadManager::CheckIfSuggestedPathExists(DownloadCreateInfo* info) {
   }
 
   // Now we return to the UI thread.
-  ui_loop_->PostTask(FROM_HERE,
+  ChromeThread::PostTask(
+      ChromeThread::UI, FROM_HERE,
       NewRunnableMethod(this,
                         &DownloadManager::OnPathExistenceAvailable,
                         info));
 }
 
 void DownloadManager::OnPathExistenceAvailable(DownloadCreateInfo* info) {
-  DCHECK(MessageLoop::current() == ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
   DCHECK(info);
 
   if (info->save_as) {
@@ -713,12 +708,11 @@ void DownloadManager::ContinueStartDownload(DownloadCreateInfo* info,
 
   // Called before DownloadFinished in order to avoid a race condition where we
   // attempt to open a completed download before it has been renamed.
-  file_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(file_manager_,
-                        &DownloadFileManager::OnFinalDownloadName,
-                        download->id(),
-                        target_path,
-                        this));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(
+          file_manager_, &DownloadFileManager::OnFinalDownloadName,
+          download->id(), target_path, this));
 
   // If the download already completed by the time we reached this point, then
   // notify observers that it did.
@@ -836,7 +830,8 @@ void DownloadManager::DownloadFinished(int32 download_id, int64 size) {
   if (download->safety_state() == DownloadItem::DANGEROUS_BUT_VALIDATED) {
     // We first need to rename the downloaded file from its temporary name to
     // its final name before we can continue.
-    file_loop_->PostTask(FROM_HERE,
+    ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
         NewRunnableMethod(
             this, &DownloadManager::ProceedWithFinishedDangerousDownload,
             download->db_handle(),
@@ -896,7 +891,8 @@ void DownloadManager::ProceedWithFinishedDangerousDownload(
     NOTREACHED();
   }
 
-  ui_loop_->PostTask(FROM_HERE,
+  ChromeThread::PostTask(
+      ChromeThread::UI, FROM_HERE,
       NewRunnableMethod(this, &DownloadManager::DangerousDownloadRenamed,
                         download_handle, success, new_path, uniquifier));
 }
@@ -964,10 +960,10 @@ void DownloadManager::DownloadCancelledInternal(int download_id,
 
   // Tell the file manager to cancel the download.
   file_manager_->RemoveDownload(download_id, this);  // On the UI thread
-  file_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(file_manager_,
-                        &DownloadFileManager::CancelDownload,
-                        download_id));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(
+          file_manager_, &DownloadFileManager::CancelDownload, download_id));
 }
 
 void DownloadManager::PauseDownload(int32 download_id, bool pause) {
@@ -1212,15 +1208,16 @@ void DownloadManager::RemoveObserver(Observer* observer) {
 // user interface.
 void DownloadManager::ShowDownloadInShell(const DownloadItem* download) {
   DCHECK(file_manager_);
-  DCHECK(MessageLoop::current() == ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
 #if defined(OS_MACOSX)
   // Mac needs to run this operation on the UI thread.
   platform_util::ShowItemInFolder(download->full_path());
 #else
-  file_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(file_manager_,
-                        &DownloadFileManager::OnShowDownloadInShell,
-                        FilePath(download->full_path())));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(
+          file_manager_, &DownloadFileManager::OnShowDownloadInShell,
+          FilePath(download->full_path())));
 #endif
 }
 
@@ -1260,15 +1257,16 @@ void DownloadManager::OpenChromeExtension(const FilePath& full_path,
 void DownloadManager::OpenDownloadInShell(const DownloadItem* download,
                                           gfx::NativeView parent_window) {
   DCHECK(file_manager_);
-  DCHECK(MessageLoop::current() == ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
 #if defined(OS_MACOSX)
   // Mac OS X requires opening downloads on the UI thread.
   platform_util::OpenItem(download->full_path());
 #else
-  file_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(file_manager_,
-                        &DownloadFileManager::OnOpenDownloadInShell,
-                        download->full_path(), download->url(), parent_window));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(
+          file_manager_, &DownloadFileManager::OnOpenDownloadInShell,
+          download->full_path(), download->url(), parent_window));
 #endif
 }
 
@@ -1407,8 +1405,9 @@ void DownloadManager::FileSelectionCanceled(void* params) {
 }
 
 void DownloadManager::DeleteDownload(const FilePath& path) {
-  file_loop_->PostTask(FROM_HERE, NewRunnableFunction(
-      &DownloadFileManager::DeleteFile, FilePath(path)));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableFunction(&DownloadFileManager::DeleteFile, FilePath(path)));
 }
 
 
@@ -1422,11 +1421,12 @@ void DownloadManager::DangerousDownloadValidated(DownloadItem* download) {
   if (download->state() != DownloadItem::COMPLETE)
     return;
 
-  file_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(this,
-                        &DownloadManager::ProceedWithFinishedDangerousDownload,
-                        download->db_handle(), download->full_path(),
-                        download->original_name()));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(
+          this, &DownloadManager::ProceedWithFinishedDangerousDownload,
+          download->db_handle(), download->full_path(),
+          download->original_name()));
 }
 
 void DownloadManager::GenerateSafeFilename(const std::string& mime_type,
diff --git a/chrome/browser/download/download_manager.h b/chrome/browser/download/download_manager.h
index 5f613a8..3974df6 100644
--- a/chrome/browser/download/download_manager.h
+++ b/chrome/browser/download/download_manager.h
@@ -59,7 +59,6 @@ class DownloadFileManager;
 class DownloadItemView;
 class DownloadManager;
 class GURL;
-class MessageLoop;
 class PrefService;
 class Profile;
 class ResourceDispatcherHost;
@@ -592,13 +591,6 @@ class DownloadManager : public base::RefCountedThreadSafe<DownloadManager>,
   // Non-owning pointer for handling file writing on the download_thread_.
   DownloadFileManager* file_manager_;
 
-  // A pointer to the main UI loop.
-  MessageLoop* ui_loop_;
-
-  // A pointer to the file thread's loop. The file thread lives longer than
-  // the DownloadManager, so this is safe to cache.
-  MessageLoop* file_loop_;
-
   // User preferences
   BooleanPrefMember prompt_for_download_;
   StringPrefMember download_path_;
diff --git a/chrome/browser/download/save_file_manager.cc b/chrome/browser/download/save_file_manager.cc
index 3289799..a985071 100644
--- a/chrome/browser/download/save_file_manager.cc
+++ b/chrome/browser/download/save_file_manager.cc
@@ -12,7 +12,7 @@
 #include "base/string_util.h"
 #include "base/task.h"
 #include "base/thread.h"
-#include "chrome/browser/browser_process.h"
+#include "chrome/browser/chrome_thread.h"
 #include "chrome/browser/download/save_file.h"
 #include "chrome/browser/download/save_package.h"
 #include "chrome/browser/net/url_request_context_getter.h"
@@ -27,25 +27,9 @@
 #include "net/url_request/url_request_context.h"
 
 
-SaveFileManager::SaveFileManager(MessageLoop* ui_loop,
-                                 MessageLoop* io_loop,
-                                 ResourceDispatcherHost* rdh)
+SaveFileManager::SaveFileManager(ResourceDispatcherHost* rdh)
     : next_id_(0),
-      ui_loop_(ui_loop),
-      io_loop_(io_loop),
       resource_dispatcher_host_(rdh) {
-  DCHECK(ui_loop_);
-  // Need to make sure that we are in UI thread because using g_browser_process
-  // on a non-UI thread can cause crashes during shutdown.
-  DCHECK_EQ(ui_loop_, MessageLoop::current());
-  // Cache the message loop of file thread.
-  base::Thread* thread = g_browser_process->file_thread();
-  if (thread)
-    file_loop_ = thread->message_loop();
-  else
-    // It could be NULL when it is created in unit test of
-    // ResourceDispatcherHost.
-    file_loop_ = NULL;
   DCHECK(resource_dispatcher_host_);
 }
 
@@ -57,16 +41,14 @@ SaveFileManager::~SaveFileManager() {
 // Called during the browser shutdown process to clean up any state (open files,
 // timers) that live on the saving thread (file thread).
 void SaveFileManager::Shutdown() {
-  MessageLoop* loop = file_loop();
-  if (loop) {
-    loop->PostTask(FROM_HERE,
-        NewRunnableMethod(this, &SaveFileManager::OnShutdown));
-  }
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(this, &SaveFileManager::OnShutdown));
 }
 
 // Stop file thread operations.
 void SaveFileManager::OnShutdown() {
-  DCHECK_EQ(MessageLoop::current(), file_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
   STLDeleteValues(&save_file_map_);
 }
 
@@ -82,14 +64,14 @@ SaveFile* SaveFileManager::LookupSaveFile(int save_id) {
 // file a request from the file thread to the IO thread to generate a
 // unique save ID.
 int SaveFileManager::GetNextId() {
-  DCHECK_EQ(MessageLoop::current(), io_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
   return next_id_++;
 }
 
 void SaveFileManager::RegisterStartingRequest(const GURL& save_url,
                                               SavePackage* save_package) {
   // Make sure it runs in the UI thread.
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
   int tab_id = save_package->tab_id();
 
   // Register this starting request.
@@ -102,7 +84,7 @@ void SaveFileManager::RegisterStartingRequest(const GURL& save_url,
 SavePackage* SaveFileManager::UnregisterStartingRequest(
     const GURL& save_url, int tab_id) {
   // Make sure it runs in UI thread.
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
 
   TabToStartingRequestsMap::iterator it = tab_starting_requests_.find(tab_id);
   if (it != tab_starting_requests_.end()) {
@@ -123,24 +105,9 @@ SavePackage* SaveFileManager::UnregisterStartingRequest(
   return NULL;
 }
 
-void SaveFileManager::RequireSaveJobFromOtherSource(SaveFileCreateInfo* info) {
-  // This function must be called on the UI thread, because the io_loop_
-  // pointer may be junk when we use it on file thread. We can only rely on the
-  // io_loop_ pointer being valid when we run code on the UI thread (or on
-  // the IO thread.
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
-  DCHECK_EQ(info->save_id, -1);
-  // Since the data will come from render process, so we need to start
-  // this kind of save job by ourself.
-  io_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(this,
-                        &SaveFileManager::OnRequireSaveJobFromOtherSource,
-                        info));
-}
-
 // Look up a SavePackage according to a save id.
 SavePackage* SaveFileManager::LookupPackage(int save_id) {
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
   SavePackageMap::iterator it = packages_.find(save_id);
   if (it != packages_.end())
     return it->second;
@@ -156,18 +123,15 @@ void SaveFileManager::SaveURL(const GURL& url,
                               const FilePath& file_full_path,
                               URLRequestContextGetter* request_context_getter,
                               SavePackage* save_package) {
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
-  if (!io_loop_) {
-    NOTREACHED();  // Net IO thread must exist.
-    return;
-  }
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
 
   // Register a saving job.
   RegisterStartingRequest(url, save_package);
   if (save_source == SaveFileCreateInfo::SAVE_FILE_FROM_NET) {
     DCHECK(url.is_valid());
 
-    io_loop_->PostTask(FROM_HERE,
+    ChromeThread::PostTask(
+        ChromeThread::IO, FROM_HERE,
         NewRunnableMethod(this,
                           &SaveFileManager::OnSaveURL,
                           url,
@@ -183,7 +147,13 @@ void SaveFileManager::SaveURL(const GURL& url,
          -1);
     info->render_process_id = render_process_host_id;
     info->render_view_id = render_view_id;
-    RequireSaveJobFromOtherSource(info);
+
+    // Since the data will come from render process, so we need to start
+    // this kind of save job by ourself.
+    ChromeThread::PostTask(
+        ChromeThread::IO, FROM_HERE,
+        NewRunnableMethod(
+            this, &SaveFileManager::OnRequireSaveJobFromOtherSource, info));
   }
 }
 
@@ -196,7 +166,7 @@ void SaveFileManager::SaveURL(const GURL& url,
 void SaveFileManager::RemoveSaveFile(int save_id, const GURL& save_url,
                                      SavePackage* package) {
   DCHECK(package);
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
   // A save page job(SavePackage) can only have one manager,
   // so remove it if it exists.
   if (save_id == -1) {
@@ -226,25 +196,19 @@ SavePackage* SaveFileManager::GetSavePackageFromRenderIds(
 // Utility function for deleting specified file.
 void SaveFileManager::DeleteDirectoryOrFile(const FilePath& full_path,
                                             bool is_dir) {
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
-  MessageLoop* loop = file_loop();
-  DCHECK(loop);
-  loop->PostTask(FROM_HERE,
-      NewRunnableMethod(this,
-                        &SaveFileManager::OnDeleteDirectoryOrFile,
-                        full_path,
-                        is_dir));
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(
+          this, &SaveFileManager::OnDeleteDirectoryOrFile, full_path, is_dir));
 }
 
 void SaveFileManager::SendCancelRequest(int save_id) {
   // Cancel the request which has specific save id.
   DCHECK_GT(save_id, -1);
-  MessageLoop* loop = file_loop();
-  DCHECK(loop);
-  loop->PostTask(FROM_HERE,
-      NewRunnableMethod(this,
-                        &SaveFileManager::CancelSave,
-                        save_id));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(this, &SaveFileManager::CancelSave, save_id));
 }
 
 // Notifications sent from the IO thread and run on the file thread:
@@ -253,17 +217,16 @@ void SaveFileManager::SendCancelRequest(int save_id) {
 // to create a SaveFile which will hold and finally destroy |info|. It will
 // then passes |info| to the UI thread for reporting saving status.
 void SaveFileManager::StartSave(SaveFileCreateInfo* info) {
-  DCHECK_EQ(MessageLoop::current(), file_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
   DCHECK(info);
   SaveFile* save_file = new SaveFile(info);
   DCHECK(!LookupSaveFile(info->save_id));
   save_file_map_[info->save_id] = save_file;
   info->path = save_file->full_path();
 
-  ui_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(this,
-                        &SaveFileManager::OnStartSave,
-                        info));
+  ChromeThread::PostTask(
+      ChromeThread::UI, FROM_HERE,
+      NewRunnableMethod(this, &SaveFileManager::OnStartSave, info));
 }
 
 // We do forward an update to the UI thread here, since we do not use timer to
@@ -273,16 +236,15 @@ void SaveFileManager::StartSave(SaveFileCreateInfo* info) {
 void SaveFileManager::UpdateSaveProgress(int save_id,
                                          net::IOBuffer* data,
                                          int data_len) {
-  DCHECK_EQ(MessageLoop::current(), file_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
   SaveFile* save_file = LookupSaveFile(save_id);
   if (save_file) {
     bool write_success = save_file->AppendDataToFile(data->data(), data_len);
-    ui_loop_->PostTask(FROM_HERE,
-        NewRunnableMethod(this,
-                          &SaveFileManager::OnUpdateSaveProgress,
-                          save_file->save_id(),
-                          save_file->bytes_so_far(),
-                          write_success));
+    ChromeThread::PostTask(
+      ChromeThread::UI, FROM_HERE,
+        NewRunnableMethod(
+            this, &SaveFileManager::OnUpdateSaveProgress, save_file->save_id(),
+            save_file->bytes_so_far(), write_success));
   }
   data->Release();
 }
@@ -297,33 +259,32 @@ void SaveFileManager::SaveFinished(int save_id,
                                    GURL save_url,
                                    int render_process_id,
                                    bool is_success) {
-  DCHECK_EQ(MessageLoop::current(), file_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
   SaveFileMap::iterator it = save_file_map_.find(save_id);
   if (it != save_file_map_.end()) {
     SaveFile* save_file = it->second;
-    ui_loop_->PostTask(FROM_HERE,
-        NewRunnableMethod(this,
-                          &SaveFileManager::OnSaveFinished,
-                          save_id,
-                          save_file->bytes_so_far(),
-                          is_success));
+    ChromeThread::PostTask(
+      ChromeThread::UI, FROM_HERE,
+        NewRunnableMethod(
+            this, &SaveFileManager::OnSaveFinished, save_id,
+            save_file->bytes_so_far(), is_success));
 
     save_file->Finish();
   } else if (save_id == -1) {
     // Before saving started, we got error. We still call finish process.
     DCHECK(!save_url.is_empty());
-    ui_loop_->PostTask(FROM_HERE,
-        NewRunnableMethod(this,
-                          &SaveFileManager::OnErrorFinished,
-                          save_url,
-                          render_process_id));
+    ChromeThread::PostTask(
+        ChromeThread::UI, FROM_HERE,
+        NewRunnableMethod(
+            this, &SaveFileManager::OnErrorFinished, save_url,
+            render_process_id));
   }
 }
 
 // Notifications sent from the file thread and run on the UI thread.
 
 void SaveFileManager::OnStartSave(const SaveFileCreateInfo* info) {
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
   SavePackage* save_package =
       GetSavePackageFromRenderIds(info->render_process_id,
                                   info->render_view_id);
@@ -357,7 +318,7 @@ void SaveFileManager::OnStartSave(const SaveFileCreateInfo* info) {
 
 void SaveFileManager::OnUpdateSaveProgress(int save_id, int64 bytes_so_far,
                                            bool write_success) {
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
   SavePackage* package = LookupPackage(save_id);
   if (package)
     package->UpdateSaveProgress(save_id, bytes_so_far, write_success);
@@ -368,30 +329,19 @@ void SaveFileManager::OnUpdateSaveProgress(int save_id, int64 bytes_so_far,
 void SaveFileManager::OnSaveFinished(int save_id,
                                      int64 bytes_so_far,
                                      bool is_success) {
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
   SavePackage* package = LookupPackage(save_id);
   if (package)
     package->SaveFinished(save_id, bytes_so_far, is_success);
 }
 
 void SaveFileManager::OnErrorFinished(GURL save_url, int tab_id) {
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
   SavePackage* save_package = UnregisterStartingRequest(save_url, tab_id);
   if (save_package)
     save_package->SaveFailed(save_url);
 }
 
-void SaveFileManager::OnCancelSaveRequest(int render_process_id,
-                                          int request_id) {
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
-  DCHECK(io_loop_);
-  io_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(this,
-                        &SaveFileManager::ExecuteCancelSaveRequest,
-                        render_process_id,
-                        request_id));
-}
-
 // Notifications sent from the UI thread and run on the IO thread.
 
 void SaveFileManager::OnSaveURL(
@@ -400,7 +350,7 @@ void SaveFileManager::OnSaveURL(
     int render_process_host_id,
     int render_view_id,
     URLRequestContextGetter* request_context_getter) {
-  DCHECK_EQ(MessageLoop::current(), io_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
   URLRequestContext* context = request_context_getter->GetURLRequestContext();
   resource_dispatcher_host_->BeginSaveFile(url,
                                            referrer,
@@ -411,22 +361,19 @@ void SaveFileManager::OnSaveURL(
 
 void SaveFileManager::OnRequireSaveJobFromOtherSource(
     SaveFileCreateInfo* info) {
-  DCHECK_EQ(MessageLoop::current(), io_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
   DCHECK_EQ(info->save_id, -1);
   // Generate a unique save id.
   info->save_id = GetNextId();
   // Start real saving action.
-  MessageLoop* loop = file_loop();
-  DCHECK(loop);
-  loop->PostTask(FROM_HERE,
-                 NewRunnableMethod(this,
-                                   &SaveFileManager::StartSave,
-                                   info));
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
+      NewRunnableMethod(this, &SaveFileManager::StartSave, info));
 }
 
 void SaveFileManager::ExecuteCancelSaveRequest(int render_process_id,
                                                int request_id) {
-  DCHECK_EQ(MessageLoop::current(), io_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::IO));
   resource_dispatcher_host_->CancelRequest(render_process_id,
                                            request_id,
                                            false);
@@ -440,7 +387,7 @@ void SaveFileManager::ExecuteCancelSaveRequest(int render_process_id,
 // sent from the UI thread, the saving job may have already completed and
 // won't exist in our map.
 void SaveFileManager::CancelSave(int save_id) {
-  DCHECK_EQ(MessageLoop::current(), file_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
   SaveFileMap::iterator it = save_file_map_.find(save_id);
   if (it != save_file_map_.end()) {
     SaveFile* save_file = it->second;
@@ -449,11 +396,11 @@ void SaveFileManager::CancelSave(int save_id) {
     // message to IO thread. If the data comes from other sources, just
     // ignore the cancel message.
     if (save_file->save_source() == SaveFileCreateInfo::SAVE_FILE_FROM_NET) {
-      ui_loop_->PostTask(FROM_HERE,
-          NewRunnableMethod(this,
-                            &SaveFileManager::OnCancelSaveRequest,
-                            save_file->render_process_id(),
-                            save_file->request_id()));
+      ChromeThread::PostTask(
+          ChromeThread::IO, FROM_HERE,
+          NewRunnableMethod(
+              this, &SaveFileManager::ExecuteCancelSaveRequest,
+              save_file->render_process_id(), save_file->request_id()));
 
       // UI thread will notify the render process to stop sending data,
       // so in here, we need not to do anything, just close the save file.
@@ -477,7 +424,7 @@ void SaveFileManager::CancelSave(int save_id) {
 void SaveFileManager::SaveLocalFile(const GURL& original_file_url,
                                     int save_id,
                                     int render_process_id) {
-  DCHECK_EQ(MessageLoop::current(), file_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
   SaveFile* save_file = LookupSaveFile(save_id);
   if (!save_file)
     return;
@@ -507,7 +454,7 @@ void SaveFileManager::SaveLocalFile(const GURL& original_file_url,
 
 void SaveFileManager::OnDeleteDirectoryOrFile(const FilePath& full_path,
                                               bool is_dir) {
-  DCHECK_EQ(MessageLoop::current(), file_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
   DCHECK(!full_path.empty());
 
   file_util::Delete(full_path, is_dir);
@@ -517,7 +464,7 @@ void SaveFileManager::OnDeleteDirectoryOrFile(const FilePath& full_path,
 // We run on this thread to avoid blocking the UI with slow Shell operations.
 #if !defined(OS_MACOSX)
 void SaveFileManager::OnShowSavedFileInShell(const FilePath full_path) {
-  DCHECK_EQ(MessageLoop::current(), file_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
   platform_util::ShowItemInFolder(full_path);
 }
 #endif
@@ -527,7 +474,7 @@ void SaveFileManager::RenameAllFiles(
     const FilePath& resource_dir,
     int render_process_id,
     int render_view_id) {
-  DCHECK_EQ(MessageLoop::current(), file_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
 
   if (!resource_dir.empty() && !file_util::PathExists(resource_dir))
     file_util::CreateDirectory(resource_dir);
@@ -544,16 +491,16 @@ void SaveFileManager::RenameAllFiles(
     }
   }
 
-  ui_loop_->PostTask(FROM_HERE,
-      NewRunnableMethod(this,
-                        &SaveFileManager::OnFinishSavePageJob,
-                        render_process_id,
-                        render_view_id));
+  ChromeThread::PostTask(
+      ChromeThread::UI, FROM_HERE,
+      NewRunnableMethod(
+          this, &SaveFileManager::OnFinishSavePageJob, render_process_id,
+          render_view_id));
 }
 
 void SaveFileManager::OnFinishSavePageJob(int render_process_id,
                                           int render_view_id) {
-  DCHECK_EQ(MessageLoop::current(), ui_loop_);
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
 
   SavePackage* save_package =
       GetSavePackageFromRenderIds(render_process_id, render_view_id);
@@ -566,7 +513,7 @@ void SaveFileManager::OnFinishSavePageJob(int render_process_id,
 
 void SaveFileManager::RemoveSavedFileFromFileMap(
     const SaveIDList& save_ids) {
-  DCHECK_EQ(MessageLoop::current(), file_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::FILE));
 
   for (SaveIDList::const_iterator i = save_ids.begin();
       i != save_ids.end(); ++i) {
diff --git a/chrome/browser/download/save_file_manager.h b/chrome/browser/download/save_file_manager.h
index 5f3d564..a77f052 100644
--- a/chrome/browser/download/save_file_manager.h
+++ b/chrome/browser/download/save_file_manager.h
@@ -72,7 +72,6 @@ class IOBuffer;
 class GURL;
 class SaveFile;
 class SavePackage;
-class MessageLoop;
 class ResourceDispatcherHost;
 class Task;
 class URLRequestContextGetter;
@@ -80,9 +79,7 @@ class URLRequestContextGetter;
 class SaveFileManager
     : public base::RefCountedThreadSafe<SaveFileManager> {
  public:
-  SaveFileManager(MessageLoop* ui_loop,
-                  MessageLoop* io_loop,
-                  ResourceDispatcherHost* rdh);
+  SaveFileManager(ResourceDispatcherHost* rdh);
   ~SaveFileManager();
 
   // Lifetime management.
@@ -127,10 +124,6 @@ class SaveFileManager
   // Helper function for deleting specified file.
   void DeleteDirectoryOrFile(const FilePath& full_path, bool is_dir);
 
-  // For posting notifications from the UI and file threads.
-  MessageLoop* ui_loop() const { return ui_loop_; }
-  MessageLoop* file_loop() const { return file_loop_; }
-
   // Runs on file thread to save a file by copying from file system when
   // original url is using file scheme.
   void SaveLocalFile(const GURL& original_file_url,
@@ -154,12 +147,6 @@ class SaveFileManager
   // A cleanup helper that runs on the file thread.
   void OnShutdown();
 
-  // The resource does not come from the network, but we still needs to call
-  // this function for getting unique save ID by calling
-  // OnRequireSaveJobFromOtherSource in the net IO thread and start saving
-  // operation. This function is called on the UI thread.
-  void RequireSaveJobFromOtherSource(SaveFileCreateInfo* info);
-
   // Called only on UI thread to get the SavePackage for a tab's profile.
   static SavePackage* GetSavePackageFromRenderIds(int render_process_id,
                                                   int review_view_id);
@@ -199,10 +186,6 @@ class SaveFileManager
   // For those requests that do not have valid save id, use
   // map:(url, SavePackage) to find the request and remove it.
   void OnErrorFinished(GURL save_url, int tab_id);
-  // Handler for a notification sent to the UI thread.
-  // The user has requested a cancel in the UI thread, so send a cancel request
-  // to stop the network requests in net IO thread.
-  void OnCancelSaveRequest(int render_process_id, int request_id);
   // Notifies SavePackage that the whole page saving job is finished.
   void OnFinishSavePageJob(int render_process_id, int render_view_id);
 
@@ -232,17 +215,6 @@ class SaveFileManager
   typedef base::hash_map<int, SaveFile*> SaveFileMap;
   SaveFileMap save_file_map_;
 
-  // Message loop that the SavePackages live on.
-  MessageLoop* ui_loop_;
-
-  // We cache the IO loop, we will use it to request resources from network.
-  MessageLoop* io_loop_;
-
-  // We cache the file loop, we will use it to do real file operation.
-  // We guarantee that we won't access them incorrectly during the shutdown
-  // process
-  MessageLoop* file_loop_;
-
   ResourceDispatcherHost* resource_dispatcher_host_;
 
   // Tracks which SavePackage to send data to, called only on UI thread.
diff --git a/chrome/browser/download/save_package.cc b/chrome/browser/download/save_package.cc
index 20cb15b..15e4787 100644
--- a/chrome/browser/download/save_package.cc
+++ b/chrome/browser/download/save_package.cc
@@ -14,6 +14,7 @@
 #include "base/task.h"
 #include "base/thread.h"
 #include "chrome/browser/browser_process.h"
+#include "chrome/browser/chrome_thread.h"
 #include "chrome/browser/download/download_item_model.h"
 #include "chrome/browser/download/download_manager.h"
 #include "chrome/browser/download/download_shelf.h"
@@ -478,7 +479,8 @@ void SavePackage::StartSave(const SaveFileCreateInfo* info) {
   // If the save source is from file system, inform SaveFileManager to copy
   // corresponding file to the file path which this SaveItem specifies.
   if (info->save_source == SaveFileCreateInfo::SAVE_FILE_FROM_FILE) {
-    file_manager_->file_loop()->PostTask(FROM_HERE,
+    ChromeThread::PostTask(
+        ChromeThread::FILE, FROM_HERE,
         NewRunnableMethod(file_manager_,
                           &SaveFileManager::SaveLocalFile,
                           save_item->url(),
@@ -584,7 +586,8 @@ void SavePackage::Stop() {
       it != saved_failed_items_.end(); ++it)
     save_ids.push_back(it->second->save_id());
 
-  file_manager_->file_loop()->PostTask(FROM_HERE,
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
       NewRunnableMethod(file_manager_,
                         &SaveFileManager::RemoveSavedFileFromFileMap,
                         save_ids));
@@ -613,7 +616,8 @@ void SavePackage::CheckFinish() {
     final_names.push_back(std::make_pair(it->first,
                                          it->second->full_path()));
 
-  file_manager_->file_loop()->PostTask(FROM_HERE,
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
       NewRunnableMethod(file_manager_,
                         &SaveFileManager::RenameAllFiles,
                         final_names,
@@ -638,7 +642,8 @@ void SavePackage::Finish() {
        it != saved_failed_items_.end(); ++it)
     save_ids.push_back(it->second->save_id());
 
-  file_manager_->file_loop()->PostTask(FROM_HERE,
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
       NewRunnableMethod(file_manager_,
                         &SaveFileManager::RemoveSavedFileFromFileMap,
                         save_ids));
@@ -734,7 +739,8 @@ void SavePackage::SaveCanceled(SaveItem* save_item) {
                                 save_item->url(),
                                 this);
   if (save_item->save_id() != -1)
-    file_manager_->file_loop()->PostTask(FROM_HERE,
+    ChromeThread::PostTask(
+        ChromeThread::FILE, FROM_HERE,
         NewRunnableMethod(file_manager_,
                           &SaveFileManager::CancelSave,
                           save_item->save_id()));
@@ -776,12 +782,13 @@ void SavePackage::SaveNextFile(bool process_all_remaining_items) {
 void SavePackage::ShowDownloadInShell() {
   DCHECK(file_manager_);
   DCHECK(finished_ && !canceled() && !saved_main_file_path_.empty());
-  DCHECK(MessageLoop::current() == file_manager_->ui_loop());
+  DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
 #if defined(OS_MACOSX)
   // Mac OS X requires opening downloads on the UI thread.
   platform_util::ShowItemInFolder(saved_main_file_path_);
 #else
-  file_manager_->file_loop()->PostTask(FROM_HERE,
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
       NewRunnableMethod(file_manager_,
                         &SaveFileManager::OnShowSavedFileInShell,
                         saved_main_file_path_));
@@ -902,7 +909,8 @@ void SavePackage::OnReceivedSerializedHtmlData(const GURL& frame_url,
   if (flag == webkit_glue::DomSerializerDelegate::ALL_FRAMES_ARE_FINISHED) {
     for (SaveUrlItemMap::iterator it = in_progress_items_.begin();
          it != in_progress_items_.end(); ++it) {
-      file_manager_->file_loop()->PostTask(FROM_HERE,
+      ChromeThread::PostTask(
+          ChromeThread::FILE, FROM_HERE,
           NewRunnableMethod(file_manager_,
                             &SaveFileManager::SaveFinished,
                             it->second->save_id(),
@@ -926,7 +934,8 @@ void SavePackage::OnReceivedSerializedHtmlData(const GURL& frame_url,
     memcpy(new_data->data(), data.data(), data.size());
 
     // Call write file functionality in file thread.
-    file_manager_->file_loop()->PostTask(FROM_HERE,
+    ChromeThread::PostTask(
+        ChromeThread::FILE, FROM_HERE,
         NewRunnableMethod(file_manager_,
                           &SaveFileManager::UpdateSaveProgress,
                           save_item->save_id(),
@@ -936,7 +945,8 @@ void SavePackage::OnReceivedSerializedHtmlData(const GURL& frame_url,
 
   // Current frame is completed saving, call finish in file thread.
   if (flag == webkit_glue::DomSerializerDelegate::CURRENT_FRAME_IS_FINISHED) {
-    file_manager_->file_loop()->PostTask(FROM_HERE,
+    ChromeThread::PostTask(
+        ChromeThread::FILE, FROM_HERE,
         NewRunnableMethod(file_manager_,
                           &SaveFileManager::SaveFinished,
                           save_item->save_id(),
@@ -1081,7 +1091,8 @@ void SavePackage::GetSaveInfo() {
   FilePath save_dir =
       GetSaveDirPreference(tab_contents_->profile()->GetPrefs());
 
-  file_manager_->file_loop()->PostTask(FROM_HERE,
+  ChromeThread::PostTask(
+      ChromeThread::FILE, FROM_HERE,
       new CreateDownloadDirectoryTask(save_dir,
           method_factory_.NewRunnableMethod(
               &SavePackage::ContinueGetSaveInfo, save_dir),