Workaround for EA-54533 - UOE: DeserializedMemberScope.getDeclarationsByLabel
Double-checked locking fixed in LockBasedStorageManager

There were two problems here:
 * a volatile field was read and then a local variable used, i.e. the field might have been changed in between the check and the return;
 * this volatile read was unnecessary, because the whole purpose of `_value` local variable is to avoid it.