Remove Profiler.getCPUProfile protocol command

CPU profile is now send to the front-end immediatly when it is ready. Protocol commands for managing CPU profiles on the back-end were removed.

BUG=327298
R=alph@chromium.org

Review URL: https://codereview.chromium.org/111343005

git-svn-id: svn://svn.chromium.org/blink/trunk@163702 bbb929c8-8fbe-4397-9dbb-9b2b20218538