Remove shouldRubberBandInDirection from the WKBundlePageUIClient

Remove shouldRubberBandInDirection from the WKBundlePageUIClient
https://bugs.webkit.org/show_bug.cgi?id=122309

Reviewed by Andreas Kling.

../WebCore:

* loader/EmptyClients.h:
* page/ChromeClient.h:
* page/FrameView.cpp:
* page/FrameView.h:
* platform/ScrollableArea.h:
* platform/mac/ScrollAnimatorMac.mm:
(WebCore::ScrollAnimatorMac::shouldRubberBandInDirection):

../WebKit/efl:

* WebCoreSupport/ChromeClientEfl.h:

../WebKit/gtk:

* WebCoreSupport/ChromeClientGtk.h:

../WebKit/mac:

* WebCoreSupport/WebChromeClient.h:

../WebKit/win:

* WebCoreSupport/WebChromeClient.h:

../WebKit/wince:

* WebCoreSupport/ChromeClientWinCE.h:

../WebKit2:

WKBundlePageUIClient's shouldRubberBandInDirection has never worked with
threaded scrolling, so remove it.

* WebProcess/InjectedBundle/API/c/WKBundlePage.h:
* WebProcess/InjectedBundle/InjectedBundlePageUIClient.cpp:
* WebProcess/InjectedBundle/InjectedBundlePageUIClient.h:
* WebProcess/WebCoreSupport/WebChromeClient.cpp:
* WebProcess/WebCoreSupport/WebChromeClient.h:

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@156871 268f45cc-cd09-0410-ab3c-d52691b4dbfc