FlameChart: convert both panes of FlameChart into View.

there are almost no business logic changes.
I moved components of both panes into their own classes
and connected them back to each other by Zoom and ChangeWindowRequest events

BUG=316167
R=yurys@chromium.org

Review URL: https://codereview.chromium.org/76533007

git-svn-id: svn://svn.chromium.org/blink/trunk@162498 bbb929c8-8fbe-4397-9dbb-9b2b20218538