Update MSE layout test expectations

Adds some crashes and failures seen during manual runs of
MediaSource layout tests on Android (309184, 303419, 323301,
323284, 302729).
Removes references for a couple MSE failures not recently
seen on flakiness dashboard (284779, 284793).

BUG=309184, 303419, 323301, 323284, 302729, 284779, 284793
TBR=acolwell@chromium.org

Review URL: https://codereview.chromium.org/113133003

git-svn-id: svn://svn.chromium.org/blink/trunk@163731 bbb929c8-8fbe-4397-9dbb-9b2b20218538