Get the NotificationPresenter from WebFrameClient instead of WebViewClient.

I'll be moving the other objects hooked on Page using Supplement in future cls. In the meantime, I made LocalFrame derive from Supplementable to support this.

BUG=304341

Review URL: https://codereview.chromium.org/232463009

git-svn-id: svn://svn.chromium.org/blink/trunk@171523 bbb929c8-8fbe-4397-9dbb-9b2b20218538