[M120 Migration][VD] Use Arrow Scroll for WebBrowser

[M120 Migration][VD] Use Arrow Scroll for WebBrowser

TV WebBrowser has a feature, use remote controller to do arrow scroll:
+ enter Key, ^ up key, v down key, > right key, < left key
         ^
         ^
       <<+>>
         v
         v
When the enter key is pressed, WebBrowser will be set to Direction Scroll Mode
if use arrow scroll feature is enabled and the web page is scrollable. And then
user can press up/down/left/right key on remote controller to scroll the web
page on different direction.

By default, TV WebBrowser capture key events and transfer
enter/up/down/left/right key events to mouse left button down/move events to
simulate the cursor's mouse down/move behaviors.

Add ewk_settings_uses_arrow_scroll_set / ewk_settings_uses_arrow_scroll_get
api to enable/disable this feature in web engine.

WebBrowser uses "run,arrow,scroll" smart callback to set the mode.

Ref:
https://review.tizen.org/gerrit/#/c/290824/

Change-Id: If15be0f144566f86efb3be812819c0a1cab4afb4
Signed-off-by: wangjing <jing124.wang@samsung.com>