https://bugs.webkit.org/show_bug.cgi?id=69127

Patch by Dongwoo Im <dw.im@samsung.com> on 2011-11-03
Reviewed by Adam Barth.

.:

Build system changes to support ENABLE(PAGE_VISIBILITY_API) on EFL port.

* Source/cmake/OptionsEfl.cmake: Add enabled ENABLE_PAGE_VISIBILITY_API definition.
* Source/cmakeconfig.h.cmake: ditto.

Source/WebKit/efl:

Implement methods to enable the Page Visibility API on EFL port.
(http://www.w3.org/TR/page-visibility)

When the visibility status of the page is changed, browser could
inform the status to WebKit using the APIs below.

* ewk/ewk_view.cpp: Add setter/getter functions to query/set page visibility state.
(ewk_view_visibility_state_set): Sets the page visibility status.
(ewk_view_visibility_state_get): Gets the page visibility status.
* ewk/ewk_view.h: Add public prototypes.

LayoutTests:

* platform/efl/Skipped: Unskip all of the test cases of page visibility.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@99155 268f45cc-cd09-0410-ab3c-d52691b4dbfc