[net] Fix parsing of HostCacheSize field trial group name.

The group name is <number><suffix>, e.g., 100A, so base::StringToSizeT will
return false.

BUG=114277,143454
TEST=chrome --force-fieldtrials=HostCacheSize/8723suffix/; open 'chrome://net-internals/#dns' and verify 'Capacity: 8723'

Review URL: https://codereview.chromium.org/11366201

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@167254 0039d316-1c4b-4281-b951-d872f2087c98
1 file changed