[dev/m42][uBrowser]Select picker doesn't work

[dev/m42][uBrowser]Select picker doesn't work

In RenderFrameImpl::OnSelectPopupMenuItems, 'external_popup_menu'
is reset when an item is selected.
This is not how the Tizen browser is supposed to behave: due to
compatibility reasons with webkit browser (kiran), chromium-efl
only close the popup when user actually dismisses it (by either
pressing "DONE" or back button). Thus, the custom behavior
is implemented on RenderFrameObserverEfl::OnSelectPopupMenuItems.

Patch fixes our select implement by making use of a
hack: in order to have access to RenderFrameImpl::external_popup_menu_
it "defines" private as public before including the associated
header. This works because RenderFrameObserver (the base class) is
declared as 'friend' to RenderFrameImpl. Thus we get access to its
private members.

Associated EWK_BRINGUP macros are also removed.

Bug: http://107.108.218.239/bugzilla/show_bug.cgi?id=12720
Change-Id: I3f2384d79da5ea7e5a2d3d696527aa19cc7d700d