DevTools: [CanvasProfiler] Follow-up UI update after recent changes to the protocol.

Quick UI update after r156003 updated the protocol.
Pending UI refresh patch: https://codereview.chromium.org/19948003/

BUG=253854
TBR=pfeldman@chromium.org

Review URL: https://codereview.chromium.org/23068002

git-svn-id: svn://svn.chromium.org/blink/trunk@156012 bbb929c8-8fbe-4397-9dbb-9b2b20218538