[File] Make MarkAsCorrupt internal
[File] Make MarkAsCorrupt internal

punker76/taglib-sharp,hwahrmann/taglib-sharp,CamargoR/taglib-sharp,archrival/taglib-sharp,Clancey/taglib-sharp,archrival/taglib-sharp,Clancey/taglib-sharp,mono/taglib-sharp,punker76/taglib-sharp,CamargoR/taglib-sharp,Clancey/taglib-sharp,hwahrmann/taglib-sharp