[DevTools] Removed ConsoleView's internal message cache.

Motivation is to move ConsoleView message filter to ConsoleModel, to propagate it to all ConsoleModel clients.

BUG=

Review URL: https://chromiumcodereview.appspot.com/18870009

git-svn-id: svn://svn.chromium.org/blink/trunk@154129 bbb929c8-8fbe-4397-9dbb-9b2b20218538