wm: Fix FD leak in watchdog when Chrome is hanging.

chrome_watchdog.cc

 // Copyright (c) 2010 The Chromium OS 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 "window_manager/chrome_watchdog.h"
 
 #include <csignal>
 
 #include <gflags/gflags.h>
 
@@ skipping 94 matching lines @@
 
   registrar_->UnregisterForWindowEvents(wm_->root());
   pinged_chrome_xid_ = 0;
   ping_timestamp_ = 0;
   wm_->event_loop()->RemoveTimeout(timeout_id_);
   timeout_id_ = -1;
 }
 
 void ChromeWatchdog::HandleTimeout() {
   DCHECK(has_outstanding_ping());
-  registrar_->UnregisterForWindowEvents(wm_->root());
-  ping_timestamp_ = 0;
-  timeout_id_ = -1;
+  DCHECK(pinged_chrome_xid_);
+  Window* win = wm_->GetWindowOrDie(pinged_chrome_xid_);
+  AbortTimeout();
 
-  Window* win = wm_->GetWindowOrDie(pinged_chrome_xid_);
   pid_t chrome_pid = static_cast<pid_t>(win->client_pid());
-
   LOG(INFO) << "Chrome window " << win->xid_str() << " didn't respond to ping; "
             << (!FLAGS_kill_chrome_if_hanging ? "(not really) " : "")
             << "sending signal " << kSignalToSend << " to PID " << chrome_pid;
   if (FLAGS_kill_chrome_if_hanging && is_pid_valid(chrome_pid)) {
     if (kill(chrome_pid, kSignalToSend) != 0)
       PLOG(ERROR) << "Unable to kill Chrome PID " << chrome_pid;
   }
 
   last_killed_pid_ = chrome_pid;
-  pinged_chrome_xid_ = 0;
 }
 
 }  // namespace window_manager