patch 7.4.2212

Problem:    Mark " is not set when closing a window in another tab. (Guraga)
Solution:   Check all tabs for the window to be valid. (based on patch by
            Hirohito Higashi, closes #974)

src/window.c

@@ -1358,7 +1358,7 @@ win_init_some(win_T *newp, win_T *oldp)
 
 #if defined(FEAT_WINDOWS) || defined(PROTO)
 /*
- * Check if "win" is a pointer to an existing window.
+ * Check if "win" is a pointer to an existing window in the current tab page.
  */
     int
 win_valid(win_T *win)
@@ -1373,6 +1373,28 @@ win_valid(win_T *win)
     return FALSE;
 }
 
+/*
+ * Check if "win" is a pointer to an existing window in any tab page.
+ */
+    int
+win_valid_any_tab(win_T *win)
+{
+    win_T	*wp;
+    tabpage_T	*tp;
+
+    if (win == NULL)
+	return FALSE;
+    FOR_ALL_TABPAGES(tp)
+    {
+	FOR_ALL_WINDOWS_IN_TAB(tp, wp)
+	{
+	    if (wp == win)
+		return TRUE;
+	}
+    }
+    return FALSE;
+}
+
 /*
  * Return the number of windows.
  */