added missing forced-flush for index cache

see http://www.yacy-forum.de/viewtopic.php?p=15732#15732

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@1434 6c8d7289-2bf4-0310-a012-ef5d649a1542

source/de/anomic/plasma/plasmaWordIndexCache.java

@@ -476,6 +476,11 @@ public final class plasmaWordIndexCache implements plasmaWordIndexInterface {
             
             // force flush (sometimes)
             if (System.currentTimeMillis() % 7 == 4) flushFromMem();
+            if (highPriority) {
+                while (cache.size() > maxWordsHigh) flushFromMem();
+            } else {
+                while (cache.size() > maxWordsLow) flushFromMem();
+            }
         }
         return added;
     }