Remove the right entries from the cache when a GC happens.

    mCache.setOnEntryRemovedListener(NULL);

    for (size_t i = 0; i < pathsToRemove.size(); i++) {

        mCache.removeAt(pathsToRemove.itemAt(i));

        // This will work because pathsToRemove is sorted

        // and because the cache is a sorted keyed vector

        mCache.removeAt(pathsToRemove.itemAt(i) - i);

    }

    mCache.setOnEntryRemovedListener(this);

}