Revert 207983 "Implement Web MIDI API back-end"

> Implement Web MIDI API back-end
> 
> This involves browser-side support and IPC for sending and receiving
> MIDI messages.  Initially support for OSX is included.
> 
> BUG=163795
> R=palmer@chromium.org, piman@chromium.org, scherkus@chromium.org
> 
> Review URL: https://codereview.chromium.org/16025005

TBR=crogers@google.com

Review URL: https://codereview.chromium.org/17334006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@207989 0039d316-1c4b-4281-b951-d872f2087c98
27 files changed