https://bugs.webkit.org/show_bug.cgi?id=127213

Patch by Yongjun Zhang <yongjun_zhang@apple.com> on 2014-01-18
Reviewed by Dan Bernstein.

Move WKRenderingProgressEvents from UIProcess to Shared, so that an inject bundle
could also use this enum when listening to layout milestones.

* Shared/API/Cocoa/WKRenderingProgressEvents.h: Added.
(NS_OPTIONS):
* Shared/API/Cocoa/WKRenderingProgressEventsInternal.h: Added.
(renderingProgressEvents):
* UIProcess/API/Cocoa/WKBrowsingContextController.h: Move WKRenderingProgressEvents to Shared/API/Cocoa/WKRenderingProgressEvents.h.
* UIProcess/API/Cocoa/WKBrowsingContextController.mm: Move renderingProgressEvents() to WKRenderingProgressEventsInternal.h.
* WebKit2.xcodeproj/project.pbxproj:
* WebProcess/InjectedBundle/API/Cocoa/WKWebProcessPlugInLoadDelegate.h: Add
    webProcessPlugInBrowserContextController:renderingProgressDidChange: to load delegate.
* WebProcess/InjectedBundle/API/mac/WKWebProcessPlugInBrowserContextController.mm:
(didLayout):
(setUpPageLoaderClient): Also listen to didLayout callback for layout milestones.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@162259 268f45cc-cd09-0410-ab3c-d52691b4dbfc