Removing PAGE_VISIBILITY_API compile guard.

Removing PAGE_VISIBILITY_API compile guard.
https://bugs.webkit.org/show_bug.cgi?id=133844

Patch by Eva Balazsfalvi <evab.u-szeged@partner.samsung.com> on 2014-06-21
Reviewed by Gavin Barraclough.

.:
* Source/cmake/OptionsEfl.cmake:
* Source/cmake/OptionsGTK.cmake:
* Source/cmake/WebKitFeatures.cmake:
* Source/cmakeconfig.h.cmake:

Source/JavaScriptCore:
* Configurations/FeatureDefines.xcconfig:

Source/WebCore:
No new tests because no functional changes.

* Configurations/FeatureDefines.xcconfig:
* Modules/vibration/NavigatorVibration.cpp:
(WebCore::NavigatorVibration::vibrate):
* dom/Document.cpp:
(WebCore::Document::hidden):
* dom/Document.h:
* dom/Document.idl:
* dom/Element.h:
* html/HTMLMediaElement.cpp:
(WebCore::HTMLMediaElement::HTMLMediaElement):
(WebCore::HTMLMediaElement::registerWithDocument):
(WebCore::HTMLMediaElement::unregisterWithDocument):
(WebCore::HTMLMediaElement::parseAttribute):
* html/HTMLMediaElement.h:
* page/Page.cpp:
(WebCore::Page::setIsVisibleInternal):
(WebCore::Page::visibilityState):
(WebCore::Page::hiddenPageCSSAnimationSuspensionStateChanged):
* page/Page.h:
* page/PageVisibilityState.cpp:
* page/PageVisibilityState.h:
* page/Settings.cpp:
(WebCore::Settings::Settings):
(WebCore::Settings::setHiddenPageCSSAnimationSuspensionEnabled):
* page/Settings.h:
* platform/audio/MediaSession.cpp:
(WebCore::MediaSession::updateClientDataBuffering):
* platform/audio/MediaSession.h:

Source/WebKit/efl:
* ewk/ewk_view.cpp:
(ewk_view_visibility_state_set):
(ewk_view_visibility_state_get):

Source/WebKit/mac:
* Configurations/FeatureDefines.xcconfig:
* WebView/WebView.mm:
(-[WebView _preferencesChanged:]):
(-[WebView _visibilityState]):

Source/WebKit2:
* Configurations/FeatureDefines.xcconfig:
* WebProcess/WebPage/WebPage.cpp:
(WebKit::WebPage::updatePreferences):

Source/WTF:
* wtf/FeatureDefines.h:

Tools:
* Scripts/webkitperl/FeatureList.pm:

WebKitLibraries:
* win/tools/vsprops/FeatureDefines.props:
* win/tools/vsprops/FeatureDefinesCairo.props:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@170235 268f45cc-cd09-0410-ab3c-d52691b4dbfc