Require FilePathWatcher destructor to be called in sequence with Watch().

chrome/common/service_process_util_posix.h

Index: chrome/common/service_process_util_posix.h
diff --git a/chrome/common/service_process_util_posix.h b/chrome/common/service_process_util_posix.h
index 2a5339e7099b48088c855868a4f2781aeb751bcf..be6ec4831ce716020a31f39dc5bbf007fb44fc26 100644
--- a/chrome/common/service_process_util_posix.h
+++ b/chrome/common/service_process_util_posix.h
@@ -12,7 +12,9 @@
 #include <memory>
 
 #include "base/callback.h"
+#include "base/memory/ref_counted.h"
 #include "base/message_loop/message_loop.h"
+#include "base/single_thread_task_runner.h"
 #include "build/build_config.h"
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
@@ -57,9 +59,9 @@ class ServiceProcessTerminateMonitor : public base::MessageLoopForIO::Watcher {
   base::Closure terminate_task_;
 };
 
-struct ServiceProcessState::StateData
-    : public base::RefCountedThreadSafe<ServiceProcessState::StateData> {
+struct ServiceProcessState::StateData {
   StateData();
+  ~StateData();
 
   // WatchFileDescriptor needs to be set up by the thread that is going
   // to be monitoring it.
@@ -70,8 +72,7 @@ struct ServiceProcessState::StateData
 
   base::ScopedCFTypeRef<CFDictionaryRef> launchd_conf;
   base::FilePathWatcher executable_watcher;
-#endif  // OS_MACOSX
-#if defined(OS_POSIX) && !defined(OS_MACOSX)
+#else
   std::unique_ptr<MultiProcessLock> initializing_lock;
   std::unique_ptr<MultiProcessLock> running_lock;
 #endif
@@ -81,9 +82,9 @@ struct ServiceProcessState::StateData
   struct sigaction old_action;
   bool set_action;
 
- protected:
-  friend class base::RefCountedThreadSafe<ServiceProcessState::StateData>;
-  virtual ~StateData();
+  // The SingleThreadTaskRunner on which SignalReady and the destructor are
+  // invoked.
+  scoped_refptr<base::SingleThreadTaskRunner> task_runner;
 };
 
 #endif  // CHROME_COMMON_SERVICE_PROCESS_UTIL_POSIX_H_