sync: Set explicit protocol_version on commit
The use of Message::Clear() function in commit.cc was unsetting this
field. This change explicitly sets the field to the current default
value following the Clear(). It also adds a test assertion to verify
that the field is properly set.
BUG=134769,134715
TEST=Run against the test server and verify the field is in the logs.
Review URL: https://chromiumcodereview.appspot.com/10679010
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@144339 0039d316-1c4b-4281-b951-d872f2087c98
2 files changed
