Provide lazy CommitPendingWrites in addition to eager SavePersistentPrefs.

chrome/browser/chromeos/cros/login_library.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/chromeos/cros/login_library.h"
 
 #include "base/message_loop.h"
+#include "base/task.h"
+#include "base/timer.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/cros/cros_library.h"
 #include "chrome/browser/chromeos/login/signed_settings_temp_storage.h"
 #include "chrome/browser/prefs/pref_service.h"
 #include "content/browser/browser_thread.h"
 #include "content/common/notification_service.h"
 #include "content/common/notification_type.h"
 
 namespace chromeos {
 
 class LoginLibraryImpl : public LoginLibrary {
  public:
   LoginLibraryImpl()
-      : set_owner_key_callback_(NULL),
+      : job_restart_request_(NULL),
+        set_owner_key_callback_(NULL),
         whitelist_op_callback_(NULL),
         property_op_callback_(NULL) {
     if (CrosLibrary::Get()->EnsureLoaded())
       Init();
   }
+
   virtual ~LoginLibraryImpl() {
     if (session_connection_) {
       chromeos::DisconnectSession(session_connection_);
     }
   }
 
   bool EmitLoginPromptReady() {
     return chromeos::EmitLoginPromptReady();
   }
 
@@ skipping 87 matching lines @@
   bool StopSession(const std::string& unique_id /* unused */) {
     // only pass unique_id through once we use it for something.
     return chromeos::StopSession("");
   }
 
   bool RestartEntd() {
     return chromeos::RestartEntd();
   }
 
   bool RestartJob(int pid, const std::string& command_line) {
-    if (g_browser_process && g_browser_process->local_state()) {
-      // XXX: normally this call must not be needed, however it turned out that
-      // without this explicit call to SavePersistentPrefs it is possible for
-      // preferences to be lost. See http://crosbug.com/13102
-      g_browser_process->local_state()->SavePersistentPrefs();
+    if (job_restart_request_) {
+      NOTREACHED();
+      return false;
     }
-    return chromeos::RestartJob(pid, command_line.c_str());
+    job_restart_request_ = new JobRestartRequest(pid, command_line);
+    return true;
   }
 
  private:
+  class JobRestartRequest
+      : public base::RefCountedThreadSafe<JobRestartRequest> {
+   public:
+    JobRestartRequest(int pid, const std::string& command_line)
+        : pid_(pid),
+          command_line_(command_line),
+          local_state_(g_browser_process->local_state()) {
+      AddRef();
+      if (local_state_) {
+        // XXX: normally this call must not be needed, however RestartJob
+        // just kills us so settings may be lost. See http://crosbug.com/13102
+        local_state_->CommitPendingWrite();
+        timer_.Start(
+            base::TimeDelta::FromSeconds(3), this,
+            &JobRestartRequest::RestartJob);
+        // Post task on file thread thus it occurs last on task queue, so it
+        // would be executed after committing pending write on file thread.
+        BrowserThread::PostTask(
+            BrowserThread::FILE, FROM_HERE,
+            NewRunnableMethod(this, &JobRestartRequest::RestartJob));
+      } else {
+        RestartJob();
+      }
+    }
+
+   private:
+    void RestartJob() {
+      if (BrowserThread::CurrentlyOn(BrowserThread::UI)) {
+        if (!chromeos::RestartJob(pid_, command_line_.c_str()))
+          NOTREACHED();
+      } else {
+        BrowserThread::PostTask(
+            BrowserThread::UI, FROM_HERE,
+            NewRunnableMethod(this, &JobRestartRequest::RestartJob));
+        MessageLoop::current()->AssertIdle();
+      }
+    }
+
+    int pid_;
+    std::string command_line_;
+    PrefService* local_state_;
+    base::OneShotTimer<JobRestartRequest> timer_;
+  };
+
   static void Handler(void* object, const OwnershipEvent& event) {
     LoginLibraryImpl* self = static_cast<LoginLibraryImpl*>(object);
     switch (event) {
       case SetKeySuccess:
         self->CompleteSetOwnerKey(true);
         break;
       case SetKeyFailure:
         self->CompleteSetOwnerKey(false);
         break;
       case WhitelistOpSuccess:
@@ skipping 47 matching lines @@
   }
 
   void CompletePropertyOp(bool result) {
     if (property_op_callback_) {
       property_op_callback_->OnComplete(result);
       property_op_callback_ = NULL;
     }
   }
 
   chromeos::SessionConnection session_connection_;
+  JobRestartRequest* job_restart_request_;
 
   Delegate* set_owner_key_callback_;
   Delegate* whitelist_op_callback_;
   Delegate* property_op_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(LoginLibraryImpl);
 };
 
 class LoginLibraryStubImpl : public LoginLibrary {
  public:
@@ skipping 57 matching lines @@
 
 // static
 LoginLibrary* LoginLibrary::GetImpl(bool stub) {
   if (stub)
     return new LoginLibraryStubImpl();
   else
     return new LoginLibraryImpl();
 }
 
 }  // namespace chromeos