[iOS][WK2] Reduce the tiling coverage to the current rect and 1 tile size ahead
https://bugs.webkit.org/show_bug.cgi?id=130555

Patch by Benjamin Poulain <bpoulain@apple.com> on 2014-03-21
Reviewed by Simon Fraser.

Source/WebCore: 

* WebCore.exp.in:
* platform/ScrollView.h:
* platform/graphics/ca/mac/TileController.mm:
(WebCore::TileController::computeTileCoverageRect):
* platform/ios/ScrollViewIOS.mm:
(WebCore::ScrollView::setScrollVelocityInformation):
(WebCore::ScrollView::computeCoverageRect):
* rendering/RenderLayerCompositor.cpp:
(WebCore::RenderLayerCompositor::flushPendingLayerChanges):

Source/WebKit2: 

* Shared/VisibleContentRectUpdateInfo.cpp:
(WebKit::VisibleContentRectUpdateInfo::encode):
(WebKit::VisibleContentRectUpdateInfo::decode):
* Shared/VisibleContentRectUpdateInfo.h:
(WebKit::VisibleContentRectUpdateInfo::VisibleContentRectUpdateInfo):
(WebKit::operator==):
* UIProcess/ios/WKContentView.mm:
(WebKit::HistoricalKinematicData::HistoricalKinematicData):
(WebKit::HistoricalKinematicData::velocityForNewData):
(WebKit::HistoricalKinematicData::clear):
(WebKit::HistoricalKinematicData::append):
(-[WKContentView didUpdateVisibleRect:unobscuredRect:scale:inStableState:]):
* WebProcess/WebPage/ViewUpdateDispatcher.cpp:
(WebKit::ViewUpdateDispatcher::visibleContentRectUpdate):
* WebProcess/WebPage/ios/WebPageIOS.mm:
(WebKit::WebPage::updateVisibleContentRects):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@166110 268f45cc-cd09-0410-ab3c-d52691b4dbfc