This deletion has several reasons:
- This code is broken and refers to non-existant private parts of dart:io
(e.g. `_NativeSocket._sockets`, `_ProcessImpl._processes`, `_RandomAccessFile._files`).
- This code is not reachable through the service protocol. `_serviceObjectHandler` uses
`paths` to fetch the right handler from `_servicePathMap` but caller `ServiceGetIOHandler`
always passes empty paths.
- The only test that was attempting to test some of this code through mirrors (sic!)
has been disabled since January 2015.
After deletion all tests continue to pass meaning that nobody really relies on this
broken code in any way.
BUG=https://github.com/dart-lang/sdk/issues/28882R=johnmccutchan@google.com
Review-Url: https://codereview.chromium.org/2715253002 .
Vyacheslav Egorov