demux: add a tail pointer for chunks
demux: add a tail pointer for chunks

a large number of non-frame chunks could slow the parse

Change-Id: I181bc73626e92263c3c5b2a6dc2bf6e6a0481d52

jacklicn/libwebp,ericmckean/webm.libwebp,ericmckean/webm.libwebp,PKRoma/libwebp,Acidburn0zzz/webm.libwebp,ya7lelkom/libwebp,jiehu5114/libwebp,kleopatra999/webm.libwebp,ericmckean/webm.libwebp,altogother/webm.libwebp,imazen/libwebp,keane83/BLE_IM,ya7lelkom/libwebp,appunite/libwebp,kalli123/webm.libwebp,yohunl/libwebp,Acidburn0zzz/webm.libwebp,Aexyn/libwebp,Maria1099/webm.libwebp,Maria1099/webm.libwebp,abwiz0086/webm.libwebp,matanbs/webm.libwebp,Aexyn/libwebp,rxl194/libwebp,PKRoma/libwebp,yohunl/libwebp,ya7lelkom/libwebp,abwiz0086/webm.libwebp,ericmckean/webm.libwebp,redengineer/libwebp,yohunl/libwebp,keane83/BLE_IM,altogother/webm.libwebp,rxl194/libwebp,reimaginemedia/webm.libwebp,Maria1099/webm.libwebp,ttyangf/libwebp,Acidburn0zzz/webm.libwebp,rxl194/libwebp,matanbs/webm.libwebp,comoyo/gonzo-libwebp,appunite/libwebp,keane83/BLE_IM,zofuthan/libwebp,Acidburn0zzz/webm.libwebp,webmproject/libwebp,kleopatra999/webm.libwebp,kleopatra999/webm.libwebp,comoyo/gonzo-libwebp,comoyo/gonzo-libwebp,comoyo/gonzo-libwebp,Aexyn/libwebp,webmproject/libwebp,imazen/libwebp,matanbs/webm.libwebp,imazen/libwebp,Suvarna1488/webm.libwebp,abwiz0086/webm.libwebp,Suvarna1488/webm.libwebp,comoyo/gonzo-libwebp,altogother/webm.libwebp,reimaginemedia/webm.libwebp,keane83/BLE_IM,ttyangf/libwebp,yohunl/libwebp,kleopatra999/webm.libwebp,jacklicn/libwebp,kleopatra999/webm.libwebp,PKRoma/libwebp,PKRoma/libwebp,Aexyn/libwebp,jacklicn/libwebp,kim42083/webm.libwebp,ya7lelkom/libwebp,abwiz0086/webm.libwebp,jiehu5114/libwebp,Suvarna1488/webm.libwebp,kim42083/webm.libwebp,jiehu5114/libwebp,kalli123/webm.libwebp,webmproject/libwebp,Suvarna1488/webm.libwebp,kalli123/webm.libwebp,ttyangf/libwebp,reimaginemedia/webm.libwebp,jacklicn/libwebp,rxl194/libwebp,redengineer/libwebp,imazen/libwebp,kim42083/webm.libwebp,kalli123/webm.libwebp,jiehu5114/libwebp,appunite/libwebp,iniwf/webm.libwebp,rxl194/libwebp,webmproject/libwebp,Suvarna1488/webm.libwebp,webmproject/libwebp,abwiz0086/webm.libwebp,gshORTON/webm.libwebp,gshORTON/webm.libwebp,altogother/webm.libwebp,kim42083/webm.libwebp,zofuthan/libwebp,jiehu5114/libwebp,ttyangf/libwebp,redengineer/libwebp,appunite/libwebp,gshORTON/webm.libwebp,zofuthan/libwebp,reimaginemedia/webm.libwebp,ttyangf/libwebp,appunite/libwebp,jacklicn/libwebp,gshORTON/webm.libwebp,iniwf/webm.libwebp,ericmckean/webm.libwebp,gshORTON/webm.libwebp,yohunl/libwebp,Maria1099/webm.libwebp,altogother/webm.libwebp,kalli123/webm.libwebp,imazen/libwebp,kim42083/webm.libwebp,matanbs/webm.libwebp,matanbs/webm.libwebp,keane83/BLE_IM,zofuthan/libwebp,reimaginemedia/webm.libwebp,Maria1099/webm.libwebp,iniwf/webm.libwebp,ya7lelkom/libwebp,redengineer/libwebp,comoyo/gonzo-libwebp,PKRoma/libwebp,PKRoma/libwebp,redengineer/libwebp,comoyo/gonzo-libwebp,zofuthan/libwebp,Aexyn/libwebp,iniwf/webm.libwebp,iniwf/webm.libwebp,Acidburn0zzz/webm.libwebp,appunite/libwebp