[sql] sql::ScopedErrorIgnorer rename to sql::test::ScopedErrorExpecter

"Ignore" was a result of focussing on avoiding the DCHECK in the
sql::Connection implementation, while "expect" focusses on what the test
is trying to do.  Changing because "ignore" is ambiguous.

BUG=597785
TBR=sdefresne@chromium.org, jam@chromium.org

Review-Url: https://codereview.chromium.org/1991503002
Cr-Commit-Position: refs/heads/master@{#400910}
22 files changed