Allow googleusercontent.com in sync tests

This change can deflake some tests.
https://chromium-swarm.appspot.com/task?id=47e99ad537e07c10
Key log:
[4056:4920:1015/120125.356:WARNING:profile_downloader.cc(250)] Loading profile data failed
[4056:4920:1015/120125.356:WARNING:profile_downloader.cc(251)]   Error: -11
[4056:4920:1015/120125.356:WARNING:profile_downloader.cc(252)]   Response code: -1
[4056:4920:1015/120125.356:WARNING:profile_downloader.cc(253)]   Url: https://lh5.googleusercontent.com/-ojmQNrzeV7Q/AAAAAAAAAAI/AAAAAAAAAAA/ACHi3rfg5XN95Zfmg7mltoIHmd3Ql0OVKw/s256-c-ns/photo.jpg
The url is actually the user's profile picture.

Bug: 1010568
Change-Id: Icc7ae2bb0599c6bdef089b66a8aa84fab7ece4c1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1864020Reviewed-by: Mikel Astiz <mastiz@chromium.org>
Commit-Queue: Sven Zheng <svenzheng@chromium.org>
Cr-Commit-Position: refs/heads/master@{#706542}

chrome/browser/sync/test/integration/sync_test.cc

@@ -1019,7 +1019,7 @@ void SyncTest::SetUpOnMainThread() {
   // Allows google.com as well as country-specific TLDs.
   host_resolver()->AllowDirectLookup("*.google.com");
   host_resolver()->AllowDirectLookup("accounts.google.*");
-
+  host_resolver()->AllowDirectLookup("*.googleusercontent.com");
   // Allow connection to googleapis.com for oauth token requests in E2E tests.
   host_resolver()->AllowDirectLookup("*.googleapis.com");