DevTools: Unflake inspector/profiler/cpu-profiler-profile-removal.html

The test callback was called from within the ProfilesPanel.showProfile()
and put the panel in a non-expected state.

BUG=378389
R=yurys@chromium.org

Review URL: https://codereview.chromium.org/306693003

git-svn-id: svn://svn.chromium.org/blink/trunk@175054 bbb929c8-8fbe-4397-9dbb-9b2b20218538