APNG + Coil, can not display with memory cache policy

[vokhuyetOz]

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Issue Info

Info	Value
Device Info	Samsung S9
System Version	Android 8.0
APNG4Android Library Version	3.0.1
Repro rate	all the time (100%)
Repro with our demo project	no
Demo project link	link to a demo project that highlights the issue

Issue Description and Steps

when i use your library to integrate apng with coil in this pull request. Decoder work well with disk cache policy. But Decoder can not get ImageSource.file() with memory cache policy

[vokhuyetOz]

https://github.com/line/apng-drawable can get image inputstream both disk cache policy and memory cache policy

[penfeizhou]

Thanks for feedback，I'll check it.

[vokhuyetOz]

@penfeizhou have you got any information about it?