Catch and suppress git clone exit code 128 (serverside error).
Catch and suppress git clone exit code 128 (serverside error).

This occurs via gerrit and manifest-versions; specifically cloning
when a git gc --auto fires serverside.

This is basically a gerrit bug, triggered via manifest-version
design flaws.

BUG=chromium-os:32377,chromium-os:32440
TEST=n/a, requires triggering a server exception for it to be testable.

Change-Id: I50ac1070678f1dff6cdc24510ff1f9e30c723c2a
Reviewed-on: https://gerrit.chromium.org/gerrit/27042
Tested-by: Brian Harring <fdc2d0a2e2340b623587cee5ea8dff425d1eb1f3@chromium.org>
Reviewed-by: Chris Sosa <959d3d631fb6f17f1b07f751372041a1edb210d1@chromium.org>
Commit-Ready: Brian Harring <fdc2d0a2e2340b623587cee5ea8dff425d1eb1f3@chromium.org>

coreos/chromite,bpsinc-native/src_third_party_chromite,bpsinc-native/src_third_party_chromite,zhang0137/chromite,chadversary/chromiumos.chromite,zhang0137/chromite,coreos/chromite,bpsinc-native/src_third_party_chromite,chadversary/chromiumos.chromite,zhang0137/chromite,coreos/chromite