Revert 184607

Revert 184607
> Remove socket_map_.size() == 0 CHECK.
>
> Remove socket_map_.size() == 0 CHECK because this causes the browser to
> crash during the shutdown if the user closes the browser without releasing
> the bluetooth socket, which I assume could happen for careless apps that did
> not properly disconnect the sockets using chrome.bluetooth.disconnect().
>
> Also I re-implemented the bluetooth socket management using API resource manager, instead of relying on bluetooth event router.
>
> BUG=135470
> TBR=sky@chromium.org
>
>
> Review URL: https://chromiumcodereview.appspot.com/12320016

TBR=youngki@chromium.org
Review URL: https://codereview.chromium.org/12328107

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@184642 0039d316-1c4b-4281-b951-d872f2087c98