Stop async spellchecker before running the leak detector.
Should a test finish up before all the spellcheck requests that
it (inadvertently?) generates have been asynchronously processed
and completed, it risks beomg reported as leaking.
These requests have no bearing on the correctness of the test
(if they did, the test would have to arrange to wait on their
outcomes), and can safely be cancelled before leak detection goes
ahead. Along with stopping the async spellchecker, this avoids
unnecessary flakiness from tests that involve spellchecking.
R=
BUG=587424
Review URL: https://codereview.chromium.org/1715203002
Cr-Commit-Position: refs/heads/master@{#376816}
10 files changed
