[WK2] Provide a mechanism to grab the back-forward list for gesture navigation purposes from another WKWebView
https://bugs.webkit.org/show_bug.cgi?id=134999
<rdar://problem/17238025>

Reviewed by Sam Weinig.

In some cases, clients may need to throw a WKWebView with no back-forward list over
another WKWebView, and want to participate in gesture swipe as if they were actually
the page being overlaid.

* UIProcess/API/Cocoa/WKWebView.mm:
(-[WKWebView setAllowsBackForwardNavigationGestures:]):
* UIProcess/API/Cocoa/WKWebViewConfiguration.mm:
(-[WKWebViewConfiguration copyWithZone:]):
(-[WKWebViewConfiguration _alternateWebViewForNavigationGestures]):
(-[WKWebViewConfiguration _setAlternateWebViewForNavigationGestures:]):
* UIProcess/API/Cocoa/WKWebViewConfigurationPrivate.h:
Keep an "alternate" WKWebView "for navigation gestures", which ViewGestureController
will use as the real source of back-forward items, and the destination of the swipe navigation.
All swipe delegate callbacks will also fire from the alternate view, because it owns the items
and will be doing the navigation.

* UIProcess/ios/ViewGestureControllerIOS.mm:
(WebKit::ViewGestureController::setAlternateBackForwardListSourceView):
(WebKit::ViewGestureController::beginSwipeGesture):
Send navigationGestureDidBegin via the alternate view's WebPageProxy if it exists.
Record a new snapshot on the current page, but copy it to the alternate view if necessary,
so that when swiping forward from the alternate view, it will have the "right" snapshot.
Get the target back forward item from the alternate view.
Send navigationGestureWillEnd via the alternate view's WebPageProxy if it exists.

(WebKit::ViewGestureController::canSwipeInDirection):
Determine if we can swipe in a direction by looking at the alternate view's back-forward list if necessary.

(WebKit::ViewGestureController::endSwipeGesture):
Send navigationGestureDidEnd via the alternate view's WebPageProxy if it exists.
Perform the navigation on the alternate view if necessary.

(WebKit::ViewGestureController::removeSwipeSnapshot):
Send navigationGestureSnapshotWasRemoved via the alternate view's WebPageProxy if it exists.

* UIProcess/mac/ViewGestureController.h:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@171219 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Fix -v|--verbose option in sort-export-file script.
https://bugs.webkit.org/show_bug.cgi?id=135043

Patch by Renato Nagy <nagy.renato@stud.u-szeged.hu> on 2014-07-18
Reviewed by Tim Horton.

-v|--verbose option does not work. Option added to getOptionsResult.

* Scripts/sort-export-file:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@171220 268f45cc-cd09-0410-ab3c-d52691b4dbfc