First round of updates in response to commenting out stale expectations.

This deletes a few tests which sound like they're wrong/buggy, and requests
rebaselines for a variety of others (or marks them expected-to-fail for
reftests).  It also restores the stale expectations for a few tests where that's
the most appropriate action.

BUG=7482,23476,243248,243732,338804,378610,396936,396940,396941,396945
TEST=none
TBR=haraken

Review URL: https://codereview.chromium.org/417873003

git-svn-id: svn://svn.chromium.org/blink/trunk@178796 bbb929c8-8fbe-4397-9dbb-9b2b20218538