This should fix T105373

See also Ia481d8a4cd9ed347874d351fa58b2712f3077a47
which is the same change on 1.26wmf14, but in a different file
because this class moved since the branch cut for wmf14.

Bug: T105373
Change-Id: Ib46e82a8c14f1f1955da268ef0ade2ab9cb39ab7

includes/db/LoadMonitorMySQL.php

@@ -84,7 +84,7 @@ class LoadMonitorMySQL implements LoadMonitor {
 			} );
 		} elseif ( $staleValue ) {
 			# Could not acquire lock but an old cache exists, so use it
-			return $value['lagTimes'];
+			return $staleValue['lagTimes'];
 		}
 
 		$lagTimes = array();