Unflake inspector/profiler/heap-snapshot-summary-search-by-id.html

There is a chance that when scrolling is required to reveal search result we can  call next() twice.

BUG=319001

Review URL: https://codereview.chromium.org/67083006

git-svn-id: svn://svn.chromium.org/blink/trunk@162266 bbb929c8-8fbe-4397-9dbb-9b2b20218538