code: public static void prependSoSource(SoSource extraSoSource) throws IOException {
      sSoSourcesLock.writeLock().lock();
      try {
        Log.d(TAG, "Prepending to SO sources: " + extraSoSource);
        assertInitialized();
        extraSoSource.prepare(makePrepareFlags());
        SoSource[] newSoSources = new SoSource[sSoSources.length + 1];
        newSoSources[0] = extraSoSource;
        System.arraycopy(sSoSources, 0, newSoSources, 1, sSoSources.length);
        sSoSources = newSoSources;
        sSoSourcesVersion++;
        Log.d(TAG, "Prepended to SO sources: " + extraSoSource);
      } finally {
        sSoSourcesLock.writeLock().unlock();
      }
    }
docs: Add a new source of native libraries. SoLoader consults the new source before any
  currently-installed source.
  
  @param extraSoSource The SoSource to install