[glib] Revert two errant commits to GMutex, etc.

[Ryan Lortie <ryanl src gnome org>]

commit 3cefb7248affdf92c878520f54bcaa3993d9b2fc
Author: Ryan Lortie <desrt desrt ca>
Date:   Mon Jul 1 23:30:31 2013 -0400

    Revert two errant commits to GMutex, etc.
    
    This reverts commits dfbac178bdcbcb042be928dcbeaa87742b511836 and
    56348210f38209a11902e54b2db41833aab36414.
    
    These two commits introduce undesirable behaviour and were made with no
    apparent approval from anybody at all, and without reference to a bug or
    mailing list discussion.

 glib/gthread-posix.c |    6 +-----
 glib/gthread-win32.c |    1 -
 2 files changed, 1 insertions(+), 6 deletions(-)
---
diff --git a/glib/gthread-posix.c b/glib/gthread-posix.c
index 403a014..23371ae 100644
--- a/glib/gthread-posix.c
+++ b/glib/gthread-posix.c
@@ -184,13 +184,12 @@ g_mutex_init (GMutex *mutex)
  * Calling g_mutex_clear() on a locked mutex leads to undefined
  * behaviour.
  *
- * Since: 2.32
+ * Sine: 2.32
  */
 void
 g_mutex_clear (GMutex *mutex)
 {
   g_mutex_impl_free (mutex->p);
-  mutex->p = NULL;
 }
 
 /**
@@ -362,7 +361,6 @@ void
 g_rec_mutex_clear (GRecMutex *rec_mutex)
 {
   g_rec_mutex_impl_free (rec_mutex->p);
-  rec_mutex->p = NULL;
 }
 
 /**
@@ -520,7 +518,6 @@ void
 g_rw_lock_clear (GRWLock *rw_lock)
 {
   g_rw_lock_impl_free (rw_lock->p);
-  rw_lock->p = NULL;
 }
 
 /**
@@ -725,7 +722,6 @@ void
 g_cond_clear (GCond *cond)
 {
   g_cond_impl_free (cond->p);
-  cond->p = NULL;
 }
 
 /**
diff --git a/glib/gthread-win32.c b/glib/gthread-win32.c
index 1f832e3..c54f2bd 100644
--- a/glib/gthread-win32.c
+++ b/glib/gthread-win32.c
@@ -198,7 +198,6 @@ void
 g_rec_mutex_clear (GRecMutex *mutex)
 {
   g_rec_mutex_impl_free (mutex->p);
-  mutex->p = NULL;
 }
 
 void