Fourth patch in getting rid of caching MessageLoop pointers.

chrome/browser/download/save_file_manager.cc

Index: chrome/browser/download/save_file_manager.cc
===================================================================
--- chrome/browser/download/save_file_manager.cc	(revision 30688)
+++ chrome/browser/download/save_file_manager.cc	(working copy)
@@ -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 @@
 // 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 @@
 // 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 @@
 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 @@
   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 @@
                               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 @@
          -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::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 @@
 // 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 @@
 // 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::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 @@
                                    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::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::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 @@
     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::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 @@
 // 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 @@
     // 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::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::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 @@
 // 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 @@
     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 @@
     }
   }
 
-  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::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) {