GitLab

Pull the implementation of TestToolbarActionsBarHelper into
BrowserActionTestUtil. The former is really only ever used
with the latter, and this allows:
- Tests to only worry about one test object.
- For one top-level fewer platform-specific test class.

TBR=sky@chromium.org (something wonky in our OWNERs check isn't counting Finnur/me as owners for toolbar actions stuff...)

Review URL: https://codereview.chromium.org/1104813005

Cr-Commit-Position: refs/heads/master@{#327134}