Increase the network performance sampling rate for MediaViewer

Since Media Viewer is a beta feature at the moment, we're
collecting too little data at the current sampling rate to make
truly informed decisions about performance. This patch changes
sampling from 1:1000 to 1:10 for non-pilot sites.

Change-Id: Ib539f96eb79707549c31cef6898920e0340e41f1
Merge "Increase the network performance sampling rate for MediaViewer"