[DevTools] Move InspectorConsoleAgent::consoleTime,count to ConsoleBase

Moved logic from InspectorConsoleAgent::consoleTime, consoleTimeEnd and consoleCount to ConsoleBase.

R=vsevik@chromium.org
BUG=408121

Review URL: https://codereview.chromium.org/530803002

git-svn-id: svn://svn.chromium.org/blink/trunk@181319 bbb929c8-8fbe-4397-9dbb-9b2b20218538