Media is encrypted but not working after cached.

Hi,

Following up on this [issue](https://github.com/danikula/AndroidVideoCache/issues/71#issuecomment-301775416)
I wrote the `Cipher` using `XOR` encryption as you said above, but i ran into problem where data is ciphered successfully and cached but not when i try to decipher the cached file.

private fun encryptOrDecrypt(input: ByteArray, key: String) {
for (i in input.indices) {
val o = input[i] xor '0'.toByte()
input[i] = o

}
}

and i aslo added the `CipherAwareCacheWrapper`

private HttpProxyCache newHttpProxyCache() throws ProxyCacheException {
HttpUrlSource source = new HttpUrlSource(url, config.sourceInfoStorage, config.headerInjector);
FileCache cache = new FileCache(config.generateCacheFile(url), config.diskUsage);
CipherAwareCacheWrapper cipherAwareCacheWrapper = new CipherAwareCacheWrapper(cache, config.cipher);
HttpProxyCache httpProxyCache = new HttpProxyCache(source, cipherAwareCacheWrapper);
httpProxyCache.registerCacheListener(uiCacheListener);
return httpProxyCache;
}

Can you please guide me on what I'm missing up?
Thanks in advance.

从提供的 newHttpProxyCache() 入口点开始，检查 CipherAwareCacheWrapper 在写入和读取缓存数据时如何应用 Cipher。使用提供的 XOR 示例重现该故障；完成标准是加密媒体在缓存后仍可读取和播放。

由索引模型根据 Issue 内容生成。