objectcache: Add WANObjectCache::TTL_NONE constant for readability

Change-Id: I07592ebb2794a7a8efc0fd1d718c1b5ca3d9b83f

diff --git a/includes/libs/objectcache/WANObjectCache.php b/includes/libs/objectcache/WANObjectCache.php
index 3099dce..e1f64ba 100755 (executable)
--- a/includes/libs/objectcache/WANObjectCache.php
+++ b/includes/libs/objectcache/WANObjectCache.php
@@ -74,6 +74,9 @@ class WANObjectCache {
        /** Seconds to keep lock keys around */
        const LOCK_TTL = 5;
 
+       /** Idiom for set()/getWithSetCallback() TTL */
+       const TTL_NONE = 0;
+
        /** Cache format version number */
        const VERSION = 1;