ANW: fix an fd leak

Change-Id: Id44cae6732c6694d2f470cbdfa5f59e7474f704f
diff --git a/include/system/window.h b/include/system/window.h
index 685e068..1e7f114 100644
--- a/include/system/window.h
+++ b/include/system/window.h
@@ -828,9 +828,8 @@
     int err = anw->dequeueBuffer(anw, anb, &fenceFd);
     if (err == 0 && fenceFd != -1) {
         err = sync_wait(fenceFd, UINT_MAX);
-        if (err == 0) {
-            close(fenceFd);
-        } else {
+        close(fenceFd);
+        if (err != 0) {
             anw->cancelBuffer(anw, *anb, fenceFd);
             *anb = NULL;
         }