Don't bother with binding null values for not-null contained entities
Don't bother with binding null values for not-null contained entities

If a contained entity is declared not null (which also happens to
be our default, because it is the most common configuration) then
we don't need to worry about testing for null and binding nulls in
the prepared statement.  All of the columns should be populated.

Signed-off-by: Shawn O. Pearce <f3ea74d906fa9fe97c1fef6bad9cb871485c7045@google.com>

CandyShop/gerrit.gwtorm,GerritCodeReview/gwtorm,thinkernel/gwtorm,evanchueng/gerrit.gwtorm,thinkernel/gwtorm,GerritCodeReview/gwtorm,1yvT0s/gerrit.gwtorm