Fix a bug where killing pages doesn't yield a sad-tab

base/process/kill.h

 // Copyright (c) 2013 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.
 
 // This file contains routines to kill processes and get the exit code and
 // termination status.
 
 #ifndef BASE_PROCESS_KILL_H_
 #define BASE_PROCESS_KILL_H_
 
@@ skipping 49 matching lines @@
 // the status returned by waitpid() on POSIX, and from
 // GetExitCodeProcess() on Windows.  |exit_code| may be NULL if the
 // caller is not interested in it.  Note that on Linux, this function
 // will only return a useful result the first time it is called after
 // the child exits (because it will reap the child and the information
 // will no longer be available).
 BASE_EXPORT TerminationStatus GetTerminationStatus(ProcessHandle handle,
                                                    int* exit_code);
 
 #if defined(OS_POSIX)
-// Wait for the process to exit and get the termination status. See
-// GetTerminationStatus for more information. On POSIX systems, we can't call
-// WaitForExitCode and then GetTerminationStatus as the child will be reaped
-// when WaitForExitCode return and this information will be lost.
-BASE_EXPORT TerminationStatus WaitForTerminationStatus(ProcessHandle handle,
-                                                       int* exit_code);
+// Send a kill signal to the process and then wait for the process to exit
+// and get the termination status.
+//
+// This is used in situations where it is believed that the process is dead
+// or dying (because communication with the child process has been cut).
+// In order to avoid erroneously returning that the process is still running
+// because the kernel is still cleaning it up, this will wait for the process
+// to terminate. In order to avoid the risk of hanging while waiting for the
+// process to terminate, send a SIGKILL to the process before waiting for the
+// termination status.
+//
+// Note that it is not an option to call WaitForExitCode and then
+// GetTerminationStatus as the child will be reaped when WaitForExitCode
+// returns, and this information will be lost.
+//
+BASE_EXPORT TerminationStatus GetKnownDeadTerminationStatus(
+    ProcessHandle handle, int* exit_code);
 #endif  // defined(OS_POSIX)
 
 // Waits for process to exit. On POSIX systems, if the process hasn't been
 // signaled then puts the exit code in |exit_code|; otherwise it's considered
 // a failure. On Windows |exit_code| is always filled. Returns true on success,
 // and closes |handle| in any case.
 BASE_EXPORT bool WaitForExitCode(ProcessHandle handle, int* exit_code);
 
 // Waits for process to exit. If it did exit within |timeout_milliseconds|,
 // then puts the exit code in |exit_code|, and returns true.
@@ skipping 49 matching lines @@
 
 #if defined(OS_POSIX) && !defined(OS_MACOSX)
 // The nicer version of EnsureProcessTerminated() that is patient and will
 // wait for |process_handle| to finish and then reap it.
 BASE_EXPORT void EnsureProcessGetsReaped(ProcessHandle process_handle);
 #endif
 
 }  // namespace base
 
 #endif  // BASE_PROCESS_KILL_H_