TimelinePanel: reduce number of resize events on initial show.

It had 3 resize events in order of constructing views.
Now it has only 2 resize events.

BUG=326121
R=pfeldman@chromium.org

Review URL: https://codereview.chromium.org/143353002

git-svn-id: svn://svn.chromium.org/blink/trunk@165405 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: extract AuditCategory to free up module descriptor.

R=apavlov@chromium.org

Review URL: https://codereview.chromium.org/142523004

git-svn-id: svn://svn.chromium.org/blink/trunk@165406 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: move shared backend settings into Settings.js.

R=yurys@chromium.org

Review URL: https://codereview.chromium.org/135993004

git-svn-id: svn://svn.chromium.org/blink/trunk@165407 bbb929c8-8fbe-4397-9dbb-9b2b20218538