Disabling the AsyncIO.IPCChannelClose UMA macro due to a potential race condition causing it to be registered from multiple threads. 
Disabling the AsyncIO.IPCChannelClose UMA macro due to a potential race condition causing it
to be registered from multiple threads. 

Logged a bug http://code.google.com/p/chromium/issues/detail?id=21827 against this and assigned
it to rvargas.

Workaround for http://b/issue?id=2111432 for now.

Bug=2111432


Review URL: http://codereview.chromium.org/204014

git-svn-id: http://src.chromium.org/svn/trunk/src@26189 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 92ffe5538186afd0116c60ed52110748564465ed
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser