Add doc precision about demux object keeping pointers to data.
Add doc precision about demux object keeping pointers to data.

Change-Id: I3d2139f975eedcce36606e586e0cbd6fa7d207e6

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