Fix crashes in FFmpegDemuxer::SetEnabled

What happens here is similar to - somehow an invalid
track id is passed from blink level down to media pipeline and we fail
to find the demuxer stream corresponding to that track id. So instead
of using map operator[], we need to use map::find and check if the
stream for the given track id was actually found.


Change-Id: Ibbffc74046a562585d6b404f90a9ae38a0d43050
Reviewed-by: Dale Curtis <>
Commit-Queue: Sergey Volk <>
Cr-Original-Commit-Position: refs/heads/master@{#534515}(cherry picked from commit 50f000d66dd5a2c512daf1fec265fc4e9668e6ab)
Reviewed-by: Sergey Volk <>
Cr-Commit-Position: refs/branch-heads/3325@{#592}
Cr-Branched-From: bc084a8b5afa3744a74927344e304c02ae54189f-refs/heads/master@{#530369}
1 file changed