Revert 236283 "Update serial API."

> Update serial API.
> 
> Undoing revert from r236265.
> 
> R=miket@chromium.org, rpaquay@chromium.org
> TBR=rch@chromium.org
> BUG=155861,148741,140125,169555,171948,281908
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=236252
> 
> Review URL: https://codereview.chromium.org/27246008

TBR=rockot@chromium.org

Review URL: https://codereview.chromium.org/79733002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@236334 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 236334