Allow to use VP8L+ICC in the same file without APLH chunk
遭遇到这个问题，其会导致某些 webp 不识别，上游并未合并，并且因为后来 golang/image 有新的安全性问题，所以就必须升级最新的代码加这个问题的解决，只得单独 fork 一份。
This repository holds supplementary Go image libraries.
The easiest way to install is to run go get -u golang.org/x/image/.... You can
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