this is a network shield alert on toolbarqueries.google.com … IIRC the server Chrome calls to accomplish web searches from the address bar, or if you want the server Chrome calls to phone home ;D
This is a known connection, and I don’t think Avast should block it 
edit: not sure why it happened on CSM site though… as this toolbarqueries thing happens constantly when using chrome (checked that a while ago with fiddler).
Report 2011-07-06 14:59:11 (GMT 1)
Website toolbarqueries.google.com
Domain Hash ad2d2e8c829f28ed39d50ba39a4e21ee
IP Address 74.125.226.146 [SCAN]
IP Hostname -
IP Country US (United States)
AS Number 15169
AS Name GOOGLE - Google Inc.
Detections 0 / 23 (0 %)
Status CLEAN
Report 2011-07-06 15:00:46 (GMT 1)
Website csmonitor.com
Domain Hash 216b6641a2e3384f9ec78757eba62cb3
IP Address 70.42.81.188 [SCAN]
IP Hostname -
IP Country US (United States)
AS Number 19024
AS Name INTERNAP-BLK5 - Internap Network Services Cor…
Detections 0 / 23 (0 %)
Status CLEAN