Create watcher when message loop is ready

atom/browser/api/atom_api_app.cc

@@ -407,11 +407,7 @@ bool NotificationCallbackWrapper(
     const base::FilePath& cwd) {
   // Make sure the callback is called after app gets ready.
   if (Browser::Get()->is_ready()) {
-    // We definitely want to call this callback on the UI thread
-    content::BrowserThread::PostTask(
-      content::BrowserThread::UI,
-      FROM_HERE,
-      base::Bind(base::IgnoreResult(callback), cmd, cwd));
+    callback.Run(cmd, cwd);
   } else {
     scoped_refptr<base::SingleThreadTaskRunner> task_runner(
         base::ThreadTaskRunnerHandle::Get());

chromium_src/chrome/browser/process_singleton_posix.cc

@@ -720,8 +720,7 @@ ProcessSingleton::ProcessSingleton(
     const base::FilePath& user_data_dir,
     const NotificationCallback& notification_callback)
     : notification_callback_(notification_callback),
-      current_pid_(base::GetCurrentProcId()),
-      watcher_(new LinuxWatcher(this)) {
+      current_pid_(base::GetCurrentProcId()) {
   // The user_data_dir may have not been created yet.
   base::CreateDirectoryAndGetError(user_data_dir, nullptr);
 
@@ -883,6 +882,7 @@ ProcessSingleton::NotifyResult ProcessSingleton::NotifyOtherProcessOrCreate() {
 }
 
 void ProcessSingleton::StartListeningOnSocket() {
+  watcher_ = new LinuxWatcher(this);
   BrowserThread::PostTask(
       BrowserThread::IO,
       FROM_HERE,
@@ -1049,7 +1049,7 @@ bool ProcessSingleton::Create() {
     NOTREACHED() << "listen failed: " << base::safe_strerror(errno);
 
   sock_ = sock;
-  
+
   if (BrowserThread::IsMessageLoopValid(BrowserThread::IO)) {
     StartListeningOnSocket();
   } else {