This CL implements the second TODO item of issue 12343:...

chrome/browser/process_singleton.h

Index: chrome/browser/process_singleton.h
===================================================================
--- chrome/browser/process_singleton.h	（版本 21941）
+++ chrome/browser/process_singleton.h	（工作副本）
@@ -92,9 +92,6 @@
   HWND remote_window_;  // The HWND_MESSAGE of another browser.
   HWND window_;  // The HWND_MESSAGE window.
 #elif defined(OS_LINUX)
-  // Set up a socket and sockaddr appropriate for messaging.
-  void SetupSocket(int* sock, struct sockaddr_un* addr);
-
   // Path in file system to the socket.
   FilePath socket_path_;
 
@@ -104,6 +101,12 @@
   scoped_refptr<LinuxWatcher> watcher_;
 #endif
 
+#if defined(OS_WIN) || defined(OS_LINUX)
+  // Timeout for the current browser process to respond. 20 seconds should be
+  // enough. It's only used in Windows and Linux implementations.
+  static const int kTimeoutInSeconds = 20;
+#endif
+
   DISALLOW_COPY_AND_ASSIGN(ProcessSingleton);
 };