Cleanup Two Obsolete Histograms

also revise an obsolete comment while I was at it

BUG=

Review URL: https://codereview.chromium.org/181313003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254055 0039d316-1c4b-4281-b951-d872f2087c98
Don't show the console window when the elevated me2me native messaging host is started.

BUG=347763

Review URL: https://codereview.chromium.org/181773009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254056 0039d316-1c4b-4281-b951-d872f2087c98
Fix HID device removal handling on Linux.

The removal handler was being short-circuited by unnecessary code,
causing removed devices to be tracked permanently and causing
chrome.hid.getDevices to leak old device IDs.

BUG=347758
TBR=rpaquay@chromium.org

Review URL: https://codereview.chromium.org/183963003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254057 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254056
SVN changes up to revision 254057