[M120 Migration][VD] Fix some focus issues for offscreen mode

[M120 Migration][VD] Fix some focus issues for offscreen mode

1.focus can't move to webview with arrow key.
  In WebBrowser, create two or more tab pages. When switch to another tab,
  the arrow key can't move to web-page. because focus isnot sync to efl window.
2.The webview focus should been controled by app through ewk_view_set focus api,
  chromium should not set default focus.
3.on hbbtv, press any key no response, because of webview on focus out status.
4.Keeps same with M94, register focusin/focusout for content_image_elm_host;
   when content_image_elm_host focusin/focusout, sync the focus to content_image.
5.Add some log for debug.

refer:
https://review.tizen.org/gerrit/#/c/297117/
https://review.tizen.org/gerrit/#/c/297301/

Change-Id: Ia2677e488c26ced5a81ae5973fc91e7789877cf2
Signed-off-by: fang fengrong <fr.fang@samsung.com>